Biomaterial Database

Studies on bacterial chemotaxis. III. Effect of methyl esters on the chemotactic response of Escherichia coli. 1979

M Ohba, and H Hayashi

The methylation-demethylation reaction of methyl-accepting chemotaxis protein (MCP) is tightly coupled to the appearance of the chemotactic response in Escherichia coli. The bacteria might therefore show a unique response upon the addition of a compound containing a methyl group. We selected methyl N-methyl anthranilate (NMMA) and its analogs for examination. When NMMA was added to a suspension of E. coli (wild type), the bacteria tumbled as it does in the presence of a repellent. NMMA caused tumbling of wild-type bacteria for at least 20 min, while a conventional repellent makes the bacteria tumble for at most one min. The effect of NMMA requires functional MCP, cheA gene product, cheB gene product, and possibly cheX gene product. A positive signal of NMMA (i.e. sudden dilution) was detected by cheZ mutants with much higher sensitivity than that of a conventional repellent, indole, while both signals were rather poorly but equally detected by cheB mutants. These results suggest that the drug is related to the function of cheB gene product, a possible demethylating enzyme of MCP.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008745	Methylation	Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)	Methylations
D002264	Carboxylic Acids	Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.	Carboxylic Acid,Acid, Carboxylic,Acids, Carboxylic
D002633	Chemotaxis	The movement of cells or organisms toward or away from a substance in response to its concentration gradient.	Haptotaxis
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D004952	Esters	Compounds derived from organic or inorganic acids in which at least one hydroxyl group is replaced by an –O-alkyl or another organic group. They can be represented by the structure formula RCOOR’ and are usually formed by the reaction between an acid and an alcohol with elimination of water.	Ester
D013045	Species Specificity	The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.	Species Specificities,Specificities, Species,Specificity, Species
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships