Antibiotic resistance in the tropics. 1. The genetics of bacterial ampicillin resistance in tropical areas.
Ampicillin and its derivatives are the most widely used beta-lactam antibiotics throughout the world. Ampicillin resistance in Gram-negative bacteria is usually manifested by plasmid-encoded beta-lactamases, which hydrolyse the beta-lactam ring of the antibiotic. There are at least 30 different plasmid-encoded beta-lactamases but almost all of them are found very infrequently. The one exception is the TEM-1 beta-lactamase which is found wherever transferable ampicillin resistance emerges and accounts for over 50% of all plasmid encoded ampicillin resistance. In India, the incidence of ampicillin resistance is high (82%) and, amongst Escherichia coli, a significant proportion of the plasmid-encoded beta-lactamases are different from those found in the United Kingdom. Although many Gram-negative species are able to accept the TEM-1 beta-lactamase, certain species have a pre-disposition to their own plasmid beta-lactamase types.
Young
H K
HK
Department of Molecular and Life Sciences, Dundee College of Technology, UK.
Nandivada
L S
LS
Amyes
S G
SG
D000668:Ampicillin Resistance / Q000235:genetics*; D004755:Enterobacteriaceae / Q000201:enzymology; D005815:Genetic Code; D007194:India; D010957:Plasmids; D014734:Vibrio cholerae / Q000187:drug effects / Q000201:enzymology; D001618:beta-Lactamases / Q000378:metabolism
D001618:beta-Lactamases; C034413:beta-lactamase TEM-1