How to Crochet a Bacteriophage Virus





Introduction: How to Crochet a Bacteriophage Virus

Bacteriophages are viruses which attach bacteria. They look so cool I just had to make one for myself. In the steps below, I will give general guidelines for crocheting one of your own. Detailed steps are not given, but it really isn't that hard if you have made crochet critters before.

Step 1: Step 1: the Head

Bacteriophage heads contain the viral DNA. They are generally depicted as an icosahedron - a solid geometric figure made up of 20 triangles. There are 5 triangles whose apexes meet at the top, 10 which circle the middle (flip every other one upside down so its base is at the top), and 5 whose apexes meet at the bottom. I used equilateral triangles for the top and bottom, and isosceles triangles twice the height of the equilateral triangles for the middle. My equilateral triangles started with 14 sc for the base and decreased to 1 sc at the apex over 13 rows. My isosceles triangles also started with a base of 14 sc, but decreased over 26 rows. It is helpful to have paper patterns to follow.  For the 5 triangles at the bottom of the icosahedron, stop with 2 sc remaining so there is an opening for the neck. When all pieces are crocheted, sew or crochet them together and stuff.

Step 2: Step 2: Add Detailing to Head

If you whip stitch the triangles together, they tend to look more like a round balloon than an icosahedron. Therefore, add some running stitches on each seam about 1/4 inch in from the edge to provide more definition. If you crochet the pieces together, you may not need this step.

Step 3: Step 3: Crochet the Collar and Sheath

Attach thread to the ring left open after sewing the head together.  Work about 10 evenly spaced sc. Now you need to increase stitches rapidly to flare out the collar. I increased 10 stitches per round for 2 rounds, then 5 stitches for 3 rounds. Crochet around for 2 rounds.  Now you need to decrease stitches. I decreased 10 stitches per round for two rounds, and another 5 stitches in the next round. Crochet around for a couple of rounds. Next, increase stitches again to form the sheath. Five increases per round for 2 rounds gave me the shape I was looking for. Finally, crochet around until the sheath is the desired length. About 30 rounds is a good length.

Step 4: Step 4: the Hexagonal Base Plate

When crocheting in the round, increases must be evenly spaced to maintain a nice circular shape. However, if you always place your increases on top of the increases from the previous round, your circle will start developing points. When you want a circle, this is not so good, but it is perfect for a hexagon. So, increase 6 stitches in the next several rounds, always placing the increases in the increases from the previous round. Repeat until the base is the desired size. My bacteriphage needed about 4 rounds. Crochet around for 1 or 2 rounds. Now you need to decrease. Place your decreases in the same locations as the increases from the previous rounds. I decreased 12 stitches in the first round, 6 stitches in the next 3 rounds,  10 stitches in the next round, and finally 5 stitches in the last round. You will need to  stuff before your hole gets too small. Finally,  add a PVC rod the length of the head and sheath to provide support. Sew the opening closed.  Unfortunately, the hexagon shape is not very visible in the picture after the other parts are added.

Step 5: Step 5: Tail Pins

Start with a 5 sc circle. Increase to 10 sc in the next round. Crochet around for 6 rounds. Stuff and sew to the bottom of the hexagonal base plate. Try to sew at the vertices of the hexagon. You will need 6 tail pins.

Step 6: Step 6: Long Tail Fibers

I don't like crocheting small diameters in the round. So, I tend to use rectangles instead. Work eight rows of 60 sc. If you work in the back loops only every other row, the rectangle will easily fold into a long rectangular prism. Insert a length of cotton cording and a piece of wire and whip stitch closed. Sew one end closed and sew the other end onto the top side of the hexagonal base plate. you will need 6 long tail fibers.

Step 7: Step 7: Add the Filaments Which Dangle From the Collar

Filaments are present on some bacteriophage viruses  and absent on others. If you would like them, work 1 row of 15 sc and sew onto collar.  You will need six. Your bacteriophage is now complete.

2 People Made This Project!


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17 Discussions

wow. well done . can you give some advice to mine. tks....

Wow cool! My company's name is It's A Virus so that would be a cool mascotte!

I am hoping to sell complete patterns on etsy in the future. Although it looks complicated, it is made entirely from single crochet: some in rows and some in the round. There are increases, which are just two stitches in one stitch from the previous round and decreases, where you pull up a loop in two stitches and pull yarn through both loops. I made a second one modifying the pattern slightly, and using just two colors. In the second one, I crocheted the triangles of the head together, which gave it a neater, more even look. I also used strips of upholstry foam combined with wire in the long tail fibers instead of cotton cording, which made them less floppy. The only other major modification was to crochet a separate piece for the bottom of the hexagonal base plate. This made inserting the PVC pipe and stuffing the sheath easier. The original is at my husband's work, but since they are a fire protection firm, his coworkers don't get it. The second is going to my son, who is a math major in college.

Oh, this is awesome - I love it!
You've inspired me to try crocheting other biologicals.  Good stuff. ;)

3 replies

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She has lots of fresh water algae too. There is also someone on etsy who has wonderful knitted representations of dissections of frogs and fetal pigs. I am constantly amazed at the creative talent out there with a scientific bent.

I remember in Discover Magazine there was a professor who crocheted universes for her classes. They were multi-dimensional, I think. In fact, the writer/journalist kept on calling it knitting even though she continually used the verb crochet...

this reminds me of a jimmy neutron episode i used to watch when i was litle with little viruses that looked like that. they like music, i think.:)

my first thought OMG it's the virus from that one episode of jimmi neutron

 I don't know  why I Think that virus is fake. It looks like it shouldn't exist.

Awesome! Briliant! What more can I say?... Love it!

Very, very cool!  Featured and rated...Now you just need to hide a small spring-loaded dagger in the tail and you can make it even more realistic!

An icosahedron has 20 equliateral triangular sides.  Since you did the counting right, that "30" in step 1 is an obvious typo.

In step 7, I think they're referred to as "filaments."  There are both filamentous and non-filamentous phages.

2 replies

Thank you very much. I'll try to edit my mistakes. I mixed up my edges with faces! Regular icosahedrons have all equilateral triangles. For non-regular ones, the triangles need not be equilateral.

Yes, indeed.  If I didn't say it before, this is a really awesome construction.