Promoters P3, Pa/Pb, P4, and P5 upstream from bla(TEM) genes and their relationship to beta-lactam resistance.
نویسندگان
چکیده
Using an isogenic system, we have determined the impact that the four promoters known to control bla(TEM) gene expression have on beta-lactamase activity. For both TEM-1 and TEM-30, this activity gradually increased in relation to the presence of promoters P3, Pa/Pb, and P4 upstream of the corresponding gene. Promoter P5, only found upstream of the bla(TEM-1B) gene, was related to the highest expression of this gene.
منابع مشابه
Variation in selected regions of blaTEM genes and promoters in Haemophilus influenzae.
OBJECTIVES To determine if the TEM beta-lactamases of Haemophilus influenzae are TEM-1 or derivatives thereof and associated exclusively with the overlapping Pa/Pb promoters. METHODS Single nucleotide specific PCR was used to discriminate the polymorphic nucleotides at positions 32 and 317 of the bla(TEM) genes of a collection of TEM-positive strains. RESULTS All bla(TEM) genes were found t...
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عنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 46 12 شماره
صفحات -
تاریخ انتشار 2002