Open AccessRegulation of Synthesis of Benzyl Alcohol Dehydrogenase in Acinetobacter calcoaceticus NCIB8250
Author(s) -
Jean D. Beggs,
Charles A. Fewson
Publication year - 1977
Publication title -
journal of general microbiology/journal of general microbiology
Language(s) - English
Resource type - Journals
eISSN - 2059-9323
pISSN - 0022-1287
DOI - 10.1099/00221287-103-1-127
Subject(s) - inducer , acinetobacter calcoaceticus , benzyl alcohol , alcohol dehydrogenase , enzyme , biochemistry , benzaldehyde , enzyme inducer , psychological repression , chemistry , dehydrogenase , alcohol , metabolism , stereochemistry , biology , acinetobacter , catalysis , gene expression , gene , antibiotics
Specific activity of benzyl alcohol dehydrogenase in carbon-limited continuous cultures was at a maximum at a specific growth rate of 0.2 h-1, but fell off at lower and higher growth rates. The specific activity in nitrogen-limited cultures was always lower and was inversely proportional to growth rate. There was severe repression of benzyl alcohol dehydrogenase during metabolism of L(+)-mandelate or phenylglyoxylate in batch cultures. Synthesis of benzyl alcohol dehydrogenase was followed in experiments where various compounds, including a gratuitous inducer and an anti-inducer of the mandelate enzymes, were added to uninduced or pre-induced cultures and to constitutive and blocked mutants. The results led to the conclusion that there were at least two types of repression. One was caused by phenylglyoxylate carbon-lyase (or a compound synthesized co-ordinately with it), but not by the other mandelate enzymes or by L(+)-mandelate, phenylglyoxylate, benzaldehyde or benzoate. A second type of repression was observed during rapid growth or after the addition of compound such as succinate which are rapidly and completely metabolized.