Chemotaxis of the marine bacterium Vibrio furnissii to sugars. A potential mechanism for initiating the chitin catabolic cascade.

Publication Year
1993

Type

Journal Article
Abstract

Immense quantities of chitin are catabolized by marine bacteria, and this process involves at least three signal transduction systems in Vibrio furnissii. One system, chemotaxis to chitin oligosaccharides, is probably used to colonize chitin particles. But how do the first few cells find this highly insoluble polysaccharide? The following hypothesis is proposed to answer this question: the bacteria respond to soluble chemo-attractants in exudates from injured organisms. Virtually all chitin-producing organisms also contain glucose and/or trehalose, often at high concentrations such as trehalose in insect hemolymph. Chemotaxis of V. furnissii was therefore studied with a variety of sugars. Fructose, ribose, and glycerol are catabolites but not attractants. The cells exhibit weak constitutive taxis to Glc and GlcNAc. After induction, they show a weak response to galactose but are strongly attracted to the following substrates of the phosphoenolpyruvate:glycose phosphotransferase system (PTS): GlcNAc, trehalose, glucose, sucrose, mannose, and mannitol. There is a rough qualitative but no quantitative correlation between the rate of phosphorylation and the chemotactic response to PTS sugars. Trehalose is especially noteworthy because it is phosphorylated at a very rapid rate by uninduced cells but is not an attractant until the cells are induced. We suggest that unidentified inducible factors link the PTS to chemotaxis.

Journal
J Biol Chem
Volume
268
Issue
13
Pages
9405-9
Date Published
1993 May 05
ISSN Number
0021-9258
Alternate Journal
J Biol Chem
PMID
8486635