Protein synthesis patterns in Acinetobacter calcoaceticus induced by phenol and catechol show specificities of responses to chemostress

Abstract

The proteins induced in Acinetobacter calcoaceticus by the potentially toxic growth substrates phenol and catechol were analyzed by 2D-electrophoresis of cell extracts and compared with those induced by heat shock and oxidative stress. Although both aromatic compounds are quite similar, the only difference being that catechol has an additional hydroxyl group, the responses obtained differed considerably. Phenol has greater lipophilicity and mainly induced heat shock proteins, whereas catechol, which causes the production of reactive oxygen species, predominantly induced oxidative stress proteins. Furthermore, some special proteins were induced by phenol or catechol, which might be useful as biomarkers for chemostress, and could be involved in the catalytic degradation of potentially toxic compounds. ß 2001 Published by Elsevier Science B.V. on behalf of the Federation of European Microbiological Societies.

Growth on Phenol at Chemostress Levels Amplifies the Expression of the Phenol Degradation Pathway in Acinetobacter calcoaceticus

“…3). Only three of the induced proteins appear to be identical to proteins previously observed following short-term treatment with phenol [4]. One of these proteins was sequenced (Tab.…”

“…For example, this technique has already been used to characterise the short-term response of Acinetobacter calcoaceticus to primary alcohols, catechol and phenol [3,4]. The comparison of protein patterns of adapted (continuously grown on 7.5 mM phenol) and non-adapted (continuously grown at low concentrations of phenol in a chemostat) cells of Acinetobacter calcoaceticus to toxic concentrations of phenol resulted in the detection of 31 proteins that were expressed at twofold higher levels, and two novel proteins (Fig.…”

“…Previous results have shown that heat shock proteins and oxidative stress proteins are induced following short-term treatment with primary alcohols, phenol and catechol [3,4]. The contribution of the well-known stress proteins to long-term stability in the presence of phenol is demonstrated, and new adaptive mechanisms that appear to be induced by an excess of toxic substrate are described.…”

“…[2], Acinetobacter calcoaceticus [3,4] and Burkholderia sp. [5], to hazardous organics at the level of protein synthesis have been published.…”

“…[5], to hazardous organics at the level of protein synthesis have been published. Proteins found to increase in level include various well-known classes of stress proteins, e.g., heat shock, oxidative stress, osmotic shock and starvation proteins [4,6,7]. Protection and stabilisation of proteins by chaperones or compatible solutes synthesised due to heat shock or osmotic stress are passive mechanisms, whereas the biocatalytically mediated removal of toxic compounds or reaction products, e.g., the elimination of oxygen radicals by catalase and superoxide dismutase, is active.…”