Week 2 HW: DNA Read, Write, and Edit

Part 1

Benchling & In-silico Gel Art

To be continued.

Part 2

No wet lab access

Part 3

DNA Design Challenge

Choose Protein

I chose the amino acid sequence of VioC - Chromobacterium violaceum for Violacein pigment.

I will reverse translate and codon optimize to amplify pigment production and thus its antimicrobial, UV-resistant properties.

sp|Q9S3U9|VIOC_CHRVO Violacein synthase OS=Chromobacterium violaceum (strain ATCC 12472 / DSM 30191 / JCM 1249 / CCUG 213 / NBRC 12614 / NCIMB 9131 / NCTC 9757 / MK) OX=243365 GN=vioC PE=1 SV=2 MKRAIIVGGGLAGGLTAIYLAKRGYEVHVVEKRGDPLRDLSSYVDVVSSRAIGVSMTVRG IKSVLAAGIPRAELDACGEPIVAMAFSVGGQYRMRELKPLEDFRPLSLNRAAFQKLLNKY ANLAGVRYYFEHKCLDVDLDGKSVLIQGKDGQPQRLQGDMIIGADGAHSAVRQAMQSGLR RFEFQQTFFRHGYKTLVLPDAQALGYRKDTLYFFGMDSGGLFAGRAATIPDGSVSIAVCL PYSGSPSLTTTDEPTMRAFFDRYFGGLPRDARDEMLRQFLAKPSNDLINVRSSTFHYKGN VLLLGDAAHATAPFLGQGMNMALEDARTFVELLDRHQGDQDKAFPEFTELRKVQADAMQD MARANYDVLSCSNPIFFMRARYTRYMHSKFPGLYPPDMAEKLYFTSEPYDRLQQIQRKQN VWYKIGRVN

Reverse translate

sp|Q9S3U9|VIOC_CHRVO Violacein synthase OS=Chromobacterium violaceum (strain ATCC 12472 / DSM 30191 / JCM 1249 / CCUG 213 / NBRC 12614 / NCIMB 9131 / NCTC 9757 / MK) OX=243365 GN=vioC PE=1 SV=2 ATGAAGCGAGCGATTATTGTCGGGGGGGGTTTAGCTGGAGGTCTAACTGCGATATACTTGGCTAAACGTGGATACGAGGT ACATGTGGTCGAGAAACGGGGCGACCCACTCAGGGACCTGTCTAGCTATGTTGATGTGGTTTCATCACGCGCAATCGGGG TCAGCATGACTGTAAGAGGCATCAAGTCAGTTTTAGCGGCCGGTATCCCCCGAGCTGAATTAGATGCCTGTGGTGAGCCA ATAGTTGCCATGGCGTTTTCCGTCGGGGGACAATATCGCATGCGGGAACTTAAACCACTCGAAGACTTCCGACCGCTTTC GCTTAACCGAGCAGCCTTCCAGAAGCTTTTGAACAAGTACGCAAACCTTGCCGGCGTACGGTACTATTTCGAACATAAAT GCCTGGATGTAGACCTGGATGGGAAATCCGTACTGATCCAAGGGAAGGACGGACAGCCGCAGCGACTTCAAGGAGATATG ATTATCGGCGCAGATGGGGCACACAGTGCAGTTCGCCAAGCGATGCAGTCAGGATTGCGGCGCTTTGAGTTTCAACAAAC GTTCTTTAGGCACGGGTATAAAACGCTGGTCCTACCCGACGCCCAAGCACTCGGGTATCGAAAGGACACGTTATATTTTT TTGGAATGGACAGCGGAGGGTTGTTCGCAGGCCGAGCCGCAACAATACCCGATGGTAGCGTGTCCATAGCTGTGTGTCTG CCCTACTCCGGCTCCCCCAGTTTGACAACCACAGATGAACCGACTATGCGTGCATTTTTCGACAGGTACTTTGGAGGTCT TCCACGGGATGCGAGGGACGAGATGCTTAGACAATTTTTAGCCAAGCCGTCTAATGATCTAATAAATGTGCGATCTTCAA CTTTTCATTACAAAGGTAACGTTCTGCTTTTAGGCGACGCCGCACATGCTACCGCGCCATTTTTAGGACAAGGCATGAAT ATGGCGTTAGAGGATGCGCGAACATTCGTAGAATTACTTGATCGCCACCAAGGCGATCAGGATAAAGCGTTTCCAGAGTT CACGGAGCTTAGAAAGGTGCAAGCGGACGCGATGCAAGATATGGCCCGGGCGAATTACGATGTTCTATCTTGCTCCAACC CGATTTTTTTTATGAGGGCGCGGTATACCCGCTACATGCACAGCAAGTTTCCGGGACTGTACCCGCCGGATATGGCCGAG AAACTGTATTTCACGTCAGAGCCGTACGATCGATTACAACAAATACAGCGCAAGCAAAACGTATGGTACAAGATAGGCAG AGTTAAT

Codon Optimize

https://en.vectorbuilder.com/tool/codon-optimization/b93b7790-7536-4d9b-a72e-02d62c3944e8.html

Next Next steps would be to embed into a seaweed matrix.

Part 4

Prepare a Twist DNA Synthesis Order

After reading more on living materials, bacterial pigments, and connecting it to my interest in light and circadian rhythms, I wanted to explore how to make a simple biological system that expresses anti-microbial or other elements only when needed, rather than all the time. So building a ’temporal’ antimicrobial system that produces a bacteria-killing peptide Magainin on a 24-hour schedule controlled by a circadian promoter RpaA. I started with just learning how to design the Magainin peptide and annotate properly.

Benchling

Twist

REF:

  1. Fang et al. (2025) - “Mechanism and reconstitution of circadian transcription in cyanobacteria”
  2. Salis et al. (2009) - “Automated Design of Synthetic Ribosome Binding Sites”
  3. Westerhoff et al. (2008) - “Structure, Membrane Orientation, Mechanism, and Function of Pexiganan (Magainin derivative)”

Part 5

DNA Read/Write/Edit

5.1 DNA Read (Sequencing)

5.1(i) What DNA would you want to sequence and why?

I would sequence my pLight-Circadian-Color plasmid (which contains the RpaA gene from Synechococcus elongatus, an anthocyanin color gene, and a light sensor) to check that it was made correctly before testing if bacteria with this plasmid change color on a 24-hour schedule when exposed to light.

5.1(ii) What sequencing technology would you use?

I would use Sanger sequencing because it’s most accurate.

5.2 DNA Write (Synthesis)

5.2(i) What DNA would you synthesize and why?

I would synthesize my yet-to-be-completed pLight-Circadian-Color plasmid containing three genes (RpaA from Synechococcus elongatus for timing, anthocyanin for color, light sensor for activation) to test if bacteria can change color on a 24-hour schedule in response to light.

5.3 DNA Edit

5.3(i) What DNA would you edit and why?

After I verify the plasmid works, I would edit the RpaA promoter to make it stronger so the color changes are brighter and more noticeable on a 24-hour schedule.

5.3(ii) What editing technology would you use?

I would use site-directed mutagenesis to make small changes to the RpaA promoter because it’s precise.