Adventures into Anatomical Crochet: Amino acids side chains

This pattern details how to make each of the 20 amino acids found in the human body. It focuses particularly on the sides groups, with the basic structure basic to all molecules being represented by a box (apart from proline). I have previously published a pattern for the basic 3D structure of amino acids.

The amino acids can be referred to in a variety of different ways. They each have a full name, and a 3 letter abbreviation, which is almost always the first 3 letters of the full name (the only exceptions are for Asparagine (Asn), Glutamine (Gln), and Isoleucine (Ile)). They also have a single-letter abbreviation, which is sometimes the first letter of the full name, but not always, since this letter needs to be unique. I have colour-coded the amino acids in this pattern so that the first letter of the colour corresponds to the single-letter abbreviation of the amino acid. This does sometimes mean that the colour names are somewhat obscure (eg. there's not many colours beginning with E), but I hope these allow you to remember the abbreviations a little better (it you need to).

The amino acids are molecules that combine together to form protein chains. There are 20 of them, and they each contain a central carbon atom attached to an amine group, a carboxyl group, a hydrogen atom, and a side chain. This side chain differs between each of the amino acids and it determines its properties. I have included fair amount of extra information about these molecules interspersed with this pattern, but if you wish to learn the basics in the form of a video, I recommend watching this video.

The crocheted section of each of the amino acids follows a very similar pattern with regards to how they are made (Proline is slightly different but not by too much). I'm hoping the written pattern will make sense on its own, but I have included a photo tutorial for Leucine so you can get more an idea of what you should be doing if you get stuck. If you are still unsure, please get in contact with me by leaving a comment below or via my Ravelry or Instagram and I'll try to help you out in any way I can.

Difficulty:

Easy - medium

You will need:

A 2.5mm crochet hook
dk yarn in black, grey, amber, violet, lime green, indigo, magenta, charcoal, white, forest green, silver, tan, yellow, khaki, red, hazel, dark brown, electric blue, navy, pink, and multicoloured.
4ply yarn in white
#8 or #10 crochet cotton in black, white, pink, yellow, and red (alternatively you can use pink, yellow, and red embroidery thread)
A darning needle
Polyester sewing cotton
A pair of scissors

Note:

'Fasten off neatly' refers to a special way of fastening off which is neater and makes it easier to see where you should be crocheting on the next round (also known as invisible fastening off). This involves pulling up your yarn through your stitch, threading the yarn underneath the second stitch from where you pulled your yarn up, then threading your yarn back through the top of this stitch and down through the back of the work. There is a very helpful site that explains it clearly found here. Just make sure when you do this that you thread your needle through the SECOND stitch after the last stitch you made, otherwise you will end up with an extra stitch which may mean that all of the following rounds are out of line with each other. The false stitch that you create is referred to in this pattern as the 'new' st. If you are unsure which stitch this is, it's the one that tightens when you pull on the loose end.

To make up:
Each amino acid should be made up in exactly the same way. After making the crocheted sections you should use crochet cotton (#10 or #8) to embroider the layout of the atoms onto both the front and back crochet sections. Carbon atoms, hydrogen atoms, and bonds should be sewn in either white or black, nitrogen atoms in pink or purple, oxygen atoms in red, and sulfur atoms in yellow (the pink, red, and yellow is needed a lot less so you can use embroidery thread for this if you'd prefer). I have included photos of both my embroidery and a drawing of the structure to help you know where the atoms should go.
After you've done this you should embroider the name of the amino acid onto one side, and then make the eyes as follows:
With black dk yarn make a magic loop with 6sc
Make a slip stitch to secure, then fasten off

Use white 4ply yarn to embroider white highlights onto the eyes, then sew these inside the rectangle without the name on it. Use black or white crochet cotton to embroider the mouth on underneath.
Sew the front and back sections together (I did this using a running stitch around the outside), stuffing the 'head' section slightly as you do so.

There are various different ways that you can classify the amino acids, and I have gone with the way I think is most straightforward.

1. Hydrocarbon side chains

The first 5 amino acids we will be looking at have side chains that are hydrocarbons, meaning that they contain only hydrogen and carbon atoms. The first 2 amino acids, glycine and alanine, are straight-chained, whereas valine, leucine, and isoleucine all have branched-chains.

Fun fact 1:

In 1969 the Merchison Metiorite fell to Earth, of which was discovered 52 different amino acids, most of which do not occur naturally on Earth.

For Glycine, G (make 2 the same):

With grey make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch4, sc in the 2nd st from hook and the next 2sts, Sc in the next 2sts of the main section, make 3sc in the next st, (sc5, make 3sc in the following st) 3 times, sc2
Round 4: sc, sc in the first 3sts up the chain sts, slip3, sc3, make 3sc in the next st, (sc7, make 3sc in the following st) 3 times, sc3
Round 5: sc in the first st
Fasten off neatly

For Alanine, A (make 2 the same):

With amber make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch7, sc in the 2nd st from hook and in the next 2 chain sts, ch4, sc in the 2nd loop from hook and in the next 2 chain sts, then sc in the remaining 3 chain sts of the ch7 section. Sc in the next 2sts of the main section, make 3sc in the next st, (sc5, make 3sc in the following st) 3 times, sc2
Round 4: sc, sc in the back loops of the first 3 chain sts of the ch7 section, ch4, sc in the 2nd loop from hook and in the next 2 chain sts, sc in the back loops of the next 3sts of the ch7 section, slip3, sc in the back loop of the next 3 chain sts, slip 6, sc3, make 3sc in the next st, (sc7, make 3sc in the following st) 3 times, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip6
Fasten off neatly

Fun fact 2:

The Hydrocarbon chain amino acids are all hydrophilic, meaning that they don't mix well with water

For valine, V (make 2 the same):

With violet make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch10, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the next 3 sts of the ch10 section, ch7, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the next 3sts of the ch7 section, sc in the next 3sts of the ch10 section, sc in the next 2sts of the main section, (make 3sc in the next st, sc5) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back loop of the first 2 chain sts, sc2tog between the back of the next 2 chain sts, sc in the back loop of the next 2 chain sts, ch4, sc in the 2nd chain st from hook and the next 2 chain sts, sc in the back loop of the next 3 sts of the ch10 section from the previous round, slip3, sc in the back loop of the next 3 chain sts, slip6, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd chain st from hook and the next 2 chain sts. Sc in the next 3 chain sts of the ch7 section from the previous round, slip3, sc in the back loop of the next 3 chain sts, slip9, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: slip6, sc in the back loop of the next 3 chain sts, slip21, sc3, slip1
Fasten off neatly

For leucine, L (make 2 the same):

With lime green make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch13, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the next 3 sts of the ch13 section (Image 1), ch7, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the next 3sts of the ch7 section (Image 2), sc in the next 3sts of the ch13 section, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the last 3sts of the ch13 section. sc in the next 2sts of the main section, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back loop of the first 3 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the back of the next 2sts of the ch13 section from the last round (Images 3/4), sc2tog between the back of the next 2 chain sts, sc in the back loop of the next 2 chain sts, ch4, sc in the 2nd chain st from hook and the next 2 chain sts, sc in the back loop of the next 3 sts of the ch13 section from the previous round, slip3, sc in the back loop of the next 3 chain sts, slip6, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd chain st from hook and the next 2 chain sts. Sc in the next 3 chain sts of the ch7 section from the previous round (Images 5/6), slip3, sc in the back loop of the next 3 chain sts, slip9, sc in the back loop of the next 3 chain sts, slip6. sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3

Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip8, sc in the back loop of the next 3 chain sts, slip21, sc in the back of the next 3 chain sts, slip3

Fasten off neatly

Image 1

Image 2

Image 3

Image 4

Image 5

Image 6

For isoleucine, I (make one of each):

For the front:

with indigo make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch10, sc in the 2nd chain st from hook and the next 2 chain sts, ch7, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd chain st from hook and the next 2 chain sts, sc in the next 3 chain sts of the ch7 section, sc in the next 3sts of the ch10 section, ch7, sc in the 2nd loop from hook and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2 chain sts, sc in the next 3 chain sts of the ch7 section, sc in the next 3sts of the ch10 section, sc in the next 2sts of the main section, (make 3sc in the following st, sc5) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back loop of the next 6 chain sts, slip3, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain sts, slip3, sc in the back of the next 3 chain sts, sc6, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc3, sc in the back of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, slip3, sc in the back of the next 3 chain sts, slip9. sc3, (make 3sc in the following st, sc7) 3 times, make 3sc in the next st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip15, sc in the back loop of the next 3sts, slip18, sc in the back of the next 3sts, slip9, sc in the back of the next 3sts, slip3
Fasten off neatly

For the back:

with indigo make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch10, sc in the 2nd chain st from hook and the next 2 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 sts of the ch10 section, ch7, sc in the 2nd st from hook and the next 2 chain sts, ch7, sc in the 2nd st from hook and the next 2 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 chain sts of the second ch7 section, then sc in the next 3 chain sts of the first ch7 section you made. Sc in the next 3sts of the ch10 section, sc in the next 2sts of the main section, (make 3sc in the following st, sc5) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back loop of the first 6 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain sts, slip3, sc in the back of the next 3 chain sts, slip6, sc in the back of the next 6 chain sts, slip3, sc in the back of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain sts. slip3, sc in the back of the next 3 chain sts, slip6, ch4, sc in the 2nd st from hook and the next 2 chain sts, slip3, ch4, sc in the 2nd st from hook and the next 2 chain sts, slip3. sc3, (make 3sc in the following st, sc7) 3 times, make 3sc in the next st, sc3
Round 5: sc, slip6, sc in the back loop of the next 3 chain sts, slip30, sc in the back of the next 3 chain sts, slip18, sc in the back loop of the next 3 chain sts, slip6, sc in the back of the next 3 chain sts, slip3
Fasten off neatly

2. The sulphur-containing side chains

Depending on which source you are looking at, the grouping of these 2 amino acids may be different. In some textbooks methionine is grouped with the 5 previous amino acids we have looked at, and they are classified together as being the hydrophobic (or non-polar) amino acids. Cysteine is also sometimes included in this classification, but this is debated, because it is able to form weak hydrogen bonds with water. (You can watch this video on Hydrogen bonds to find out more if you're interested)

For methionine, M (make 2 the same):

With magenta make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc
Round 3: sc, ch16, sc in the 2nd chain st from hook and the next 2 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 6 sts of the ch16 section, (ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 sts of the ch16 section) twice, sc2, (make 3sc in the first st, sc5) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back loop of the next 6 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back loop of the next 3 chain sts, slip3, sc in the back loop of the next 3 chain sts, slip9, sc in the back loop of the next 3 chain sts, slip6, sc in the back loop of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip6, sc in the back loop of the next 3 chain sts, slip9, sc in the back loop of the next 3 chain sts, slip3
Fasten off neatly

For cysteine, C (make 2 the same):

with charcoal make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc
Round 3: sc, ch10, sc in the 2nd st from hook and in the next 5 chain sts, ch4, sc in the 2nd loop from hook and in the next 2 chain sts, then sc in the remaining 3 chain sts of the ch7 section. Sc in the next 2sts of the main section, make 3sc in the next st, (sc5, make 3sc in the following st) 3 times, sc2
Round 4: sc, sc in the back loops of the first 3 chain sts of the ch10 section, ch4, sc in the 2nd loop from hook and in the next 2 chain sts, sc in the back loops of the next 6sts of the ch10 section, slip6, sc in the back loop of the next 3 chain sts, slip 6, sc3, make 3sc in the next st, (sc7, make 3sc in the following st) 3 times, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip6
Fasten off neatly

Fun fact 3:
The terminal -SH group of cysteine means that 2 cysteine molecules are able to form a covalent bonds between the sulphur atoms, known as a disulphide bond. This is particularly important regarding the structure of certain proteins. The 3D structure of proteins is held in place mostly by non-covalent forces of attraction between the amino acids, but these disulphide bonds are also present in some proteins to stabilise they structure further. Eg. insulin contains 3 disulphide bonds that help to keep it rigid.

3. The aromatic amino acids

Aromatic molecules are those containing a benzene ring. There are 3 of these, phynylalanine, Tyrosine, and Tryptophan. However, I have included tyrosine under the alcohols group, since it contains an -OH group.
Whilst phynylalanine is hydrophilic, the other two amino acids are less easily classified. The -OH group of tyrosine is able to form hydrogen bonds with water, as is the nitrogen atom of tryptophan. Whilst this makes the molecules somewhat hydrophilic, the large benzene rings are very hydrophobic, meaning that the overall classification of the molecules is up for debate.

For tryptophan, W:

For the benzene ring (make 2):
With white make a magic loop with 6sc
Round 1: make 2sc in each st (12sc)
Round 2: (sc, make 2sc in the next st) 6 times (18sc)
Round 3: (sc2, make 2sc in the next st) 6 times (24sc)
Fasten off neatly

For the nitrogen ring (make 2):
With white make a magic loop with 5sc
Round 1: make 2sc in each st (10sc)
Round 2: (sc, make 2sc in the next st) 5 times (15sc)
Round 3: ch4, sc in the 2nd st from hook and the next 2 chain sts, (sc2, make 2sc in the following st) 5 times
sc in the back of the 3 chain sts
Fasten off neatly

For the front:
With white make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch6, slip the 14th st from the new st of the nitrogen ring, slip the next 17sts, slip the 3rd st after the new st of the benzene ring, then slip19, skip 4sts on the nitrogen ring, then slip the next 4sts, sc in the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 chain sts, sc2, make 3sc in the next st, (sc5, make 3sc in the following st) 3 times, sc2
Round 4: sc, sc3 in the back of the chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain sts, slip45, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc3 in the back loops of the chain sts.
Fasten off neatly

For the back:
With white make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch6, slip the 10th st from the new st of the nitrogen ring, slip the next 3sts, slip the 3rd st after the new st of the benzene ring, then slip19, skip 4sts on the nitrogen ring, then slip the next 18sts, sc in the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 chain sts, sc2, make 3sc in the next st, (sc5, make 3sc in the following st) 3 times, sc2
Round 4: sc, sc3 in the back of the chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain sts, slip45, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc3 in the back loops of the chain sts.
Fasten off neatly

For Phenylalanine, F (Make 2 the same):

For the benzene ring:
With forest green make a magic loop with 6sc
Round 1: make 2sc in each st (12sc)
Round 2: (sc, make 2sc in the next st) 6 times (18sc)
Fasten off neatly

For the main section:
With forest green make a magic loop with 8sc
Round 1: (sc, maeke 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch6, sc in the 3rd st after the new st you made when fastening off neatly on the benzne ring, sc in the next st, make 2sc in the following st, (sc2, make 2sc in the next st) 5 times, sc in the first 3 chain sts back down the ch6 section, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 chain sts of the ch6 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 4 chain sts, slip27, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back of the next 3 chain sts, slip3
Fasten off

4. The alcohol side chains

In organic chemistry the -OH group is known as the alcohol group. This group makes the following amino acids hydrophilic (apart from possibly tyrosine, see section 3 description), as they can form hydrogen bonds with water.

For serine, S:

For the front:

With silver make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc
Round 3: sc, ch7, sc in the 2nd st from hook and the next 2 chain sts, ch5, sc in the 2nd st from hook and the next 3 chain sts, sc in the next 3 chain sts of the ch7 section, sc2, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain sts, slip3, sc in the back of the next 4 chain sts, slip7, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip3
Fasten off neatly

For the back:
With silver make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc
Round 3: sc, ch7, sc in the 2nd st from hook and the next 2 chain sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the next 3 chain sts of the ch7 section, sc2, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back of the first 3 chain sts, ch5, sc in the 2nd st from hook and the next 3 chain sts, sc in the back of the next 3 chain sts, slip3, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 4 chain sts, slip3
Fasten off neatly

For Threonine, T (make 2 the same):

With tan make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) x3, make 3sc in the next st, sc (24sc)
Round 3: sc, ch10, sc in the 2nd loop from hook and the next 2sts, ch4, sc in the 2nd loop from hook and the next 2sts, sc in the next 3sts of the chain 10 section, ch5, sc in the 2nd loop from hook and the next 3sts, sc in the next 3sts of the ch10 section, sc2, (make 3sc in the next st, sc7) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts,sc in the back loop of the next 3 chain sts, slip3, sc inthe back loop of the next 3 chain sts, slip6, sc in the back loop of the next 4 chain sts, slip7, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip6, sc in the back loop of the next 3 chain st, slip3
Fasten off neatly

For Tyrosine, Y (make 2 the same):

For the benzene ring:
With yellow make a magic loop with 6sc
Round 1: make 2sc in each st (12sc)
Round 2: (sc, make 2sc in the next st) 6 times (18sc)
Fasten off neatly

For the main section:

with yellow make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) x3, make 3sc in the next st, sc (24sc)
Round 3: sc, ch6, sc in the third st from the 'new' st in the benzene ring, sc, make 2sc in the next st, (sc2, make 2sc in the next st) twice, ch5, sc in the 2nd st from hook and the next 3sts, (sc2, make 2sc in the next st) 3 times around the benzene ring, sc3 down the ch6 section, ch4, sc in the 2nd st from hook and the next 2sts, sc int he next 3 chian sts of the ch6 section, sc2, (make 3sc in the next st, sc7) 3 times, make 3sc in the next st, sc2
Round 4: sc, sc in the back loop of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back loop of the next 3 chain sts, slip12, sc in the back of the next 4 chain sts, slip19, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip3
Fasten off neatly

5. The charged side chains

These are sub-divided into 2 groups, the acidic, negatively charged amino acids, and those that are basic (positively charged).

In this context, acidic means that the amino acid is able to donate a proton (hydrogen ion) from solution, and basic means that it is able to accept a proton from solution. The forms given in this pattern are the forms they would be found in aqueous solution. That is, they have accepted or donated their proton and become charged. Aspartic acid and glutamic acid are known as aspartate and glutamate when in their ionised forms. Be careful not to confuse these with the amide derivatives asparagine and glutamine, given in part 6.

For Lysine, K (make 2 the same):

With Khaki make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the next st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch19, sc in the 2nd st from hook and the next 2 chain sts, (ch4, sc in the 2nd st from hook and the next 2sts) twice, (sc in the next 3 chain sts of the ch19 section, ch4, sc in the 2nd st from hook and the next 2sts) 4 times, sc in the next 3sts of the ch19 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, (sc in the back loop of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts) 5 times, (sc in the back loop of the next 3 chain sts, slip3) twice, (slip3, sc in the back of the next 3 chain sts, slip3) 4 times, slip3, sc3, (make 3sc in the next, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, (sc in the back of the next 3 chain sts, slip6) 4 times, sc in the back loop of the next 3 chain sts, slip3
Fasten off neatly

For Arganine, R:

For the front:

With red make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the next st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch22, sc in the 2nd loop and the next 2 chain sts, ch4, sc in the 2nd loop from hook and the next 2sts, sc in the next 3 sts of the ch22 section, ch7, sc in the 2nd loop from hook and the next 2sts, ch4, sc in the 2nd loop from hook and the next 2sts, sc in the next 3sts of the ch7 section, sc in the next 6sts of the ch22 section, (ch4, sc in the 2nd loop from hook and the next 2sts, sc in the next 3sts of the ch22 section) 3 times, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, (sc in the back of the next 3 chain sts of the ch22 section, ch4, sc in the 2nd st from hook and the next 2sts) 4 times, sc in the back of the next 2 chain sts of the chain 22 section, sc2tog between the next 2 chain sts, sc in the back of the next chain st, sc2tog between the next 2 chain sts, sc in the back of the next 2 chain sts, slip3, sc in the back of the next 3 chain sts, slip6, sc in the back of the next 2 chain sts, sc2tog in the back of the next 2 chain sts, sc in the back of the next 2 chain sts, slip3, sc in the back of the next 3 chain sts, slip12, (sc in the back of the next 3 chain sts, slip6) 3 times, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, (slip3, sc in the back of the next 3 chain sts, slip3) 4 times
Fasten off neatly

For the back:
With red make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the next st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch22, sc in the 2nd loop and the next 2 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 sts of the ch22 section, ch7, sc in the 2nd st from hook and the next 2sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3sts of the ch7 section, sc in the next 3sts of the ch22 section, (ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3sts of the ch22 section) 4 times, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, (sc in the back of the next 3 chain sts of the ch22 section, ch4, sc in the 2nd st from hook and the next 2sts) 3 times, sc in the back of the next 5 chain sts, sc2tog between the next 2 chain sts, sc in the back of the next chain st, sc2tog between the next 2 chain sts, sc in the back of the next 2 chain sts, slip3, sc in the back of the next 3 chain sts, slip6, sc in the back of the next 2 chain sts, sc2tog in the back of the next 2 chain sts, sc in the back of the next 2 chain sts, slip3, sc in the back of the next 3 chain sts, slip9, (sc in the back of the next 3 chain sts, slip6) 4 times, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, (slip3, sc in the back of the next 3 chain sts, slip3) 3 times
Fasten off neatly

For histidine, H:

For the ring (make 2):
With hazel make a magic loop with 5sc
Round 1: make 2sc in each st (10sc)
Round 2: (sc, make 2sc in the next st) 5 times (15sc)
Fasten off

For the front:
With hazel make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the next st, sc3) 3 times, make 3sc in the following st, sc (24sc)
Round 3: Sc, ch4, sc in the small section you made in the 2nd st from the 'new' st created when fastening off neatly and the next 3sts, ch6, sc in the 2nd st from hook and the next 2sts, sc in the same st as before the chain sts, sc2, make 2sc in the next st, sc3, ch4, sc in the 2nd st from hook and the next 2sts, sc in the same st as before the chain sts, sc2, make 2sc in the next st, sc2, sc in the same st as the first st you crocheted into on the small section, sc in the next 3 chain sts of the 6 chain sts you made earlier on in this round, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 chain sts of the ch6 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2

Round 4: sc, sc in the back of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back of the next 3 chain sts, slip4, sc in the back of the next 3 chain sts, slip12, sc in the back of the next 3 chain sts, slip14, sc in the back of the next 3 chain sts , slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: Sc, slip3, sc in the back of the next 3 chain sts, slip3
Fasten off neatly

For the back:
With hazel make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the next st, sc3) 3 times, make 3sc in the following st, sc (24sc)
Round 3: Sc, ch6, sc in the ring in the 2nd st from the 'new' st and the next 2sts, make 2sc in the next st, sc3, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the same st as the one you crocheted into before you made the chain sts, sc2, make 2sc in the next st, sc3, ch4, sc in the 2nd st from hook and the next 2sts, sc in the same st as before the chain sts, sc2, sc in the same st as the first st you crocheted into on the ring, sc in the first 3 chain sts of the ch6 you made at the start of this round, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 chain sts of the ch6 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: Sc, sc3, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back of the first 3 chain sts of the ch6 section, slip8, sc in teh back of the next 3 chain sts of the ch6 section, slip11, sc in the back of the next 3 chain sts, slip10, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the first st, sc7) 3 times, make 3sc in the next st, sc3
Round 5: Sc, slip3 up the chain, slip3

Fasten off

For Aspartate, D:

For the front:

With dark brown make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)

Round 3: sc, ch11, sc in the 2nd st from hook, sc in the next 2 chain sts, sc2tog, sc in the next 2sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3sts of the chain 11 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, ch4, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 4 chain sts, slip6, sc in the back loop of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip5, sc2tog between the next st and the next chain st, sc in the next 2 chain sts, slip3
Fasten off neatly

For the back:

with dark brown make a magic loop with 8sc

Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch10, sc in the 2nd st from hook and the next chain st, sc2tog, sc in the next 2 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back of the next 3 chain sts of the ch10 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back of next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back of the next 3 chain sts, ch5, sc in the 2nd st from hook and the next 2 chain sts, sc in the back of the next 3 chain st, slip5, sc in the back loop of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip5, sc2tog between the next st and the following chain st, sc in the back of the next 3 chain sts, slip4
Fasten off neatly

For glutamate (glutamic acid), E:

For the front:
With electric blue make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch13, sc in the 2nd st from hook and the next 2 chain sts, ch5, sc in the 2nd st from hook and the next 2 chain sts, sc2tog between the following 2 chian sts, sc in the next 2 chain sts, (ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 chain sts of the ch13 section) twice, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, (sc in the back of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts) twice, sc in the back of the next 2 chain sts, sc2tog, sc in the back of the next 2 chain sts, slip3, sc in the back of the next 4 chain sts, slip7, (sc in the back of the first 3 chain sts, slip6) twice, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back of the next 3 chain sts, slip6, sc in the back of the next 3 chain sts, slip3
Fasten off neatly

For the back:
with electric blue make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch14, sc in the 2nd st from hook and the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 3 chain sts, sc2tog, sc in the next 2 chain sts, (ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 chain sts of the ch13 section) twice, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc int he following st, sc2
Round 4: sc, (sc in the back of the first 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts) twice, sc in the back of the next 2 chain sts, sc2tog, sc in the back of the next 3 chain sts, slip4, sc in the back of the next 3 chain sts, slip6, (sc in the back of the first 3 chain sts, slip6) twice, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc int he following st, sc3
Round 5: sc, slip3, sc in the back of the next 3 chain sts, slip6, sc in the back of the next 3 chain sts, slip3
Fasten off neatly

6. The amide derivatives

For Asparagine, N:

For the front:

With navy make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch13, sc in the 2nd chain st from hook and the next chain st, sc2tog, sc in the next 2 chain sts, ch5, sc in the 2nd chain st from hook and the next 3 chain sts, sc in the next 3 chain sts of the ch13 section, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 chain sts of the ch13 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back loop of the first 3 chain sts of the ch13 section, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back loop of the next 6 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back loop of the next 3 chain sts, slip5, sc in the back of the next 4 sts, slip7, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back loop of the next 3 chain sts, slip8, sc2tog between the next st and the back loop of the following chain st, sc in the back loop of the next 2 chain sts, slip3
Fasten off

For the back:
With navy make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch11, sc in the 2nd st from hook and the next 3 chain sts, ch7, sc in the 2nd chain st from hook and the next chain st, sc2tog, sc in the next 2 sts of the ch7 section, then sc in the next 3sts of the ch11 section, ch4, sc in the 2nd st from hook and the next 2sts, sc in the next 3 chain sts of the ch13 section, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the following st, sc2
Round 4: sc, sc in the back loop of the first 3 chain sts of the ch13 section, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back loop of the next 3 chain sts, sc in the back loop of the next 4 chain sts, slip4, sc in the back of the next 3 chain sts, ch4, sc in the 2nd st from hook and the next 2sts, sc in the back loop of the next 3 chain sts, slip8, sc in the back of the next 3 chain sts, slip6, sc3, (make 3sc in the next st, sc7) 3 times, make 3sc in the following st, sc3
Round 5: sc, slip3, sc in the back of the next 3 chain sts, slip16, sc2tog between the next st and the back loop of the following chain st, sc in the back loop of the next 2 chain sts, slip3
Fasten off

For glutamine, Q:

For the front:

With multicoloured yarn make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch16, sc in the 2nd loop from hook and the next 2sts, ch4, sc in the 2nd st from hook and the next st, sc2tog between the next chain st and the following chain st of the ch16 section, sc2 down the chain, (ch4, sc in the 2nd loop from hook and the next 4 chain sts, sc in the next 3 chain sts down the ch16 section) 3 times, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the follwing st, sc2
Round 4: sc, (sc3 up the chain, ch4, sc in the 2nd st from hook and the next st) twice, sc5, sc2tog, sc2, slip3, sc in the back of the next 3 chain sts, slip5, (sc in the back of the next 3 chain sts, slip6) 3 times, sc3, (make 3sc in the first st, sc7) 3 times, make 3sc in the next st, sc3
Round 5: sc, (slip3, sc in the back of the 3 chain sts, slip3) twice

For the back:
With mulicoloured yarn make a magic loop with 8sc
Round 1: (sc, make 3sc in the next st) 4 times (16sc)
Round 2: sc2, (make 3sc in the first st, sc3) 3 times, make 3sc in the next st, sc (24sc)
Round 3: sc, ch16, scin the 2nd loop from hook and the next 2sts, ch4, sc in the 2nd st from hook and the next st, sc2tog between the next chain st and the following chain st of the ch16 section, sc5 down the chain, (ch4, sc in the 2nd loop from hook and the next 4 chain sts, sc in teh next 3 chain sts down the ch16 section twice, sc2, (make 3sc in the next st, sc5) 3 times, make 3sc in the follwing st, sc2
Round 4: sc, (sc3 up the chain, ch4, sc in the 2nd st from hook and the next st) 3 times, sc2, sc2tog, sc2, slip3, sc in the back of the next 3 chain sts, slip8, (sc in the back loops of the next 3 chain sts, slip6) twice, sc3, (make 3sc in the first st, sc7) 3 times, make 3sc in the next st, sc3
Round 5: sc, (slip3, sc in the back of the 3 chain sts, slip3) 3 times

7. Proline, P
Technically proline isn't an amino acid, although it is commonly referred to as such as it can combine with the 19 other amino acids to form protein chains. Oficially it is an imino acid, since it contains an imine (NH2) group in place of the usual amine (NH3) group. Because of this it forms a cyclical structure, as can be seen below.

For the front:
With pink make a magic loop with 5sc
Round 1: make 2sc in each st (10sc)
Round 2: (sc, make 2sc in the next st) 5 times (15sc)
Round 3: (sc2, make 2sc inthe following st) 5 times (20sc)
Round 4: sc4, ch8, sc in the 2nd chain st from hook and the next 2 chain sts, sc2tog between the following 2 chain sts, sc in the next 2 chain sts, sc in the same st as the last one you crocheted into before the ch8, (sc4, ch4, sc in the 2nd st from hook and the next 3 chain sts, sc in the same st as you crocheted into before the ch4) 4 times, sc3
Round 5: sc, sc in the first 3 chain sts, ch4, sc in the 2nd chain st from hook and the next 2 chain sts, sc in the back of the next 4 chain sts of the ch7 section, slip6, (sc5, sc in the back loop of the next 3 chain sts, slip3) 4 times, sc4
Round 5: sc, slip3, sc in the back of the next 4 chain sts, slip4
Fasten off neatly

For the back:
With pink make a magic loop with 5sc
Round 1: make 2sc in each st (10sc)
Round 2: (sc, make 2sc in the next st) 5 times (15sc)
Round 3: (sc2, make 2sc inthe following st) 5 times (20sc)
Round 4: sc4, ch7, sc in the 2nd chain st from hook and the next chain st, sc2tog in between the following 2 chain sts, sc in the next 2 chain sts, sc in the same st as the last one you crocheted into before the ch7, (sc4, ch4, sc in the 2nd st from hook and the next 3 chain sts, sc in the same st as you crocheted into before the ch4) 4 times, sc3
Round 5: sc, sc in the first 3 chain sts, ch5, sc in the 2nd chain st from hook and the next 3 chain sts, sc in the back of the next 3 chain sts of the ch6 section, slip5, (sc5, sc in the back loop of the next 3 chain sts, slip3) 4 times, sc4
Round 6: sc, slip3, sc in the back of the next 3 chain sts, slip3
Fasten off neatly

That's all from this pattern - I hope you have found it interesting! If you have any questions please feel free to contact me, either by leaving a comment below or via my Ravelry or Instagram pages. You can also follow me on there to keep up to date with the latest projects I'm working on. You are very welcome to sell finished products, but I do ask that you don't re-post this pattern or claim it as your own. Thank you!