Adrian P V, DU Plessis M, Klugman K P, Amyes S G
Department of Medical Microbiology, University of the Witwatersrand, and the South African Institute for Medical Research, Johannesburg, South Africa.
Antimicrob Agents Chemother. 1998 Sep;42(9):2221-4. doi: 10.1128/AAC.42.9.2221.
The nucleotide sequence of a plasmid-borne trimethoprim resistance gene from a commensal fecal Escherichia coli isolate revealed a new dihydrofolate reductase gene, dfrXV, which occurred as a gene cassette integrated in a site-specific manner in a class 1 integron. The new gene shows 84% nucleotide identity and the predicted protein shows 90% amino acid identity with dfrI and DHFR type I, respectively. Genes for spectinomycin resistance, aadA1 [ant (3")-Ia], and sulfonamide resistance, sulI, were located downstream of dfrXV in a manner identical to that in pLMO229.
一株共生粪便大肠杆菌分离株中质粒携带的甲氧苄啶抗性基因的核苷酸序列揭示了一个新的二氢叶酸还原酶基因dfrXV，它作为一个基因盒以位点特异性方式整合在1类整合子中。该新基因与dfrI和I型二氢叶酸还原酶（DHFR）的核苷酸同一性分别为84%，预测的蛋白质与它们的氨基酸同一性分别为90%。壮观霉素抗性基因aadA1 [ant(3")-Ia]和磺胺抗性基因sulI以与pLMO229中相同的方式位于dfrXV下游。
