https://pages.htgaa.org/2026b/joe-perez/week-02-hw-dna-design/index.htmlPart 1 — Define your expression target What molecule are you expressing? For this assignment, I would focus on expressing ACC deaminase, an enzyme encoded by the acdS gene. My larger project from Homework #1 was a microbial inoculant for corn, beans, and squash that could potentially help the plants with nutrient availability and environmental stresses such as drought and flooding. A complete inoculant would probably involve several microorganisms and biological functions, which would be too complicated to design as one genetic construct. For this homework, I am therefore focusing on one possible part of that system. ACC deaminase breaks down ACC (1-aminocyclopropane-1-carboxylate), which is involved in the plant’s production of the stress-related hormone ethylene. My idea is that a plant-associated bacterium expressing ACC deaminase could potentially help moderate plant stress responses. I do not expect this single enzyme to make corn, beans, or squash drought- or flood-resistant by itself. Instead, it would be one possible function in the larger microbial community proposed in Homework #1. What is the sequence? I would use the acdS gene encoding ACC deaminase from Pseudomonas putida UW4. The protein is 338 amino acids long, and its reviewed UniProt accession is Q5PWZ8. The corresponding genomic sequence is associated with GenBank accession AF047710. UniProt For Kernel, I would import the natural acdS sequence and then use Kernel’s codon-optimization tool for my chosen host rather than trying to design the protein myself. What host or chassis? For the assignment, I would use Pseudomonas putida as the bacterial host. I chose a bacterial host because the final product from Homework #1 is supposed to be a microbial soil/root inoculant. Pseudomonas species are common in plant-associated microbial research, and the original acdS gene I selected already comes from a P. putida strain. This also keeps my first genetic design relatively simple rather than trying to engineer the plant itself. Where does the product need to go? I would keep ACC deaminase inside the bacterial cell (cytoplasm). Because of this, I would not initially add a secretion signal peptide. The bacteria would colonize the area around or near plant roots and express the enzyme themselves.Hugoen