|
type |
Journal Article |
authors |
Tobin, M.B.; Kovacevic, S.; Madduri, K.; Hoskins, J.A.; Skatrud, P.L.; Vining, L.C.; Stuttard, C.; Miller, J.R. |
title |
Localization of the lysine epsilon-aminotransferase (lat) and delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine synthetase (pcbAB) genes from Streptomyces clavuligerus and production of lysine epsilon-aminotransferase activity in Escherichia coli |
journal |
J Bacteriol |
Activity |
2.6.1.36 |
Family |
2.6.1.36.a |
sel |
selected |
ui |
1917855 |
year |
(1991) |
volume |
173 |
number |
19 |
pages |
6223-9 |
| |
keywords |
Binding Sites |
abstract |
Lysine epsilon-aminotransferase (LAT) in the beta-lactam-producing actinomycetes is considered to be the first step in the antibiotic biosynthetic pathway. Cloning of restriction fragments from Streptomyces clavuligerus, a beta-lactam producer, into Streptomyces lividans, a nonproducer that lacks LAT activity, led to the production of LAT in the host. DNA sequencing of restriction fragments containing the putative lat gene revealed a single open reading frame encoding a polypeptide with an approximately Mr 49,000. Expression of this coding sequence in Escherichia coli led to the production of LAT activity. Hence, LAT activity in S. clavuligerus is derived from a single polypeptide. A second open reading frame began immediately downstream from lat. Comparison of this partial sequence with the sequences of delta-(L-alpha-aminoadipyl)-L-cysteinyl-D valine (ACV) synthetases from Penicillium chrysogenum and Cephalosporium acremonium and with nonribosomal peptide synthetases (gramicidin S and tyrocidine synthetases) found similarities among the open reading frames. Since mapping of the putative N and C termini of S. clavuligerus pcbAB suggests that the coding region occupies approximately 12 kbp and codes for a polypeptide related in size to the fungal ACV synthetases, the molecular characterization of the beta-lactam biosynthetic cluster between pcbC and cefE (approximately 25 kbp) is nearly complete. |
last changed |
2009/04/30 14:51 |
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