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Enzymic assays for isomers of 2,6-diaminopimelic acid in walls of Bacillus cereus and Bacillus megaterium.

ABSTRACT: An enzymic assay for individual isomers (meso-, LL- and DD-) of 2,6-diaminopimelate was developed. The enzyme 2,6-diaminopimelate decarboxylase specifically attacked meso-diaminopimelate and was used to measure this isomer manometrically. The meso- and LL-isomers were measured together manometrically in a coupled assay with diaminopimelate decarboxylase and diaminopimelate epimerase (which converts LL-diaminopimelate into meso-diaminopimelate). The DD-isomer was not attacked by either enzyme and was measured, as residual diaminopimelate after the coupled assay, by a colorimetric method, which was also used to measure total diaminopimelate before enzymic treatments. The coupled enzymes were also used to prepare pure DD-isomer from chemically synthesized diaminopimelate. A mixture of diaminopimelate isomers was present in walls of four strains of Bacillus megaterium [in each about 75% (w/w) meso-, 18% LL- and 7% DD-] and in walls of two strains of Bacillus cereus (about 85% meso-, 8% LL- and 7% DD-). One strain of B. cereus contained at least 95% meso-diaminopimelate, with only traces of LL- and DD-isomers. Peptidoglycan from Escherichia coli was assayed as containing at least 95% meso-isomer. The proportion of isomers in the wall of a strain of B. megaterium remained constant after growth in a variety of different media.

SUBMITTER: Day A

PROVIDER: S-EPMC1164555 | biostudies-other | 1977 Mar

REPOSITORIES: biostudies-other

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Isomers of glucosaminylphospatiylglycerol in Bacillus megaterium.

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| S-EPMC1184863 | biostudies-other

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| S-EPMC9133035 | biostudies-literature

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| S-EPMC1178406 | biostudies-other

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| S-EPMC2798246 | biostudies-literature

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Comparative transcriptome and phenotype analysis of acid-stressed Bacillus cereus strains

Project description:This SuperSeries is composed of the SubSeries listed below.

2009-11-25 | GSE13773 | GEO

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Project description:Comparative Genomic Hybridization. Analysis of genomic content of closely related Bacillus species. Refer to individual records for strain information. Refer to platform and individual sample records for experimental protocols. Keywords: other

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| S-EPMC9281120 | biostudies-literature

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