The sul2 gene similarly encodes a sulfonamide-resistant dihydropteroate synthase (distinct from sul1). It is frequently found on small plasmids in Gram-negative bacteria. Detection of sul2 indicates sulfonamide resistance; like sul1, it means that therapy with trimethoprim-sulfamethoxazole will likely be ineffective. Its presence (often with sul1) reinforces the prediction of sulfonamide/trimethoprim resistance and suggests the need for alternative antibiotic choices (Partridgeet al. 2018, Sköld 2000, Sköld 2010).
Partridge, S. R., Kwong, S. M., Firth, N., & Jensen, S. O. (2018). Mobile Genetic Elements Associated with Antimicrobial Resistance. Clinical microbiology reviews, 31(4), e00088-17. https://doi.org/10.1128/CMR.00088-17
Sköld O. (2000). Sulfonamide resistance: mechanisms and trends. Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy, 3(3), 155–160. https://doi.org/10.1054/drup.2000.0146
Sköld O. (2010). Sulfonamides and trimethoprim. Expert review of anti-infective therapy, 8(1), 1–6.
