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Occurrence of free D-amino acids and aspartate racemases in hyperthermophilic archaea.

ABSTRACT: The occurrence of free D-amino acids and aspartate racemases in several hyperthermophilic archaea was investigated. Aspartic acid in all the hyperthermophilic archaea was highly racemized. The ratio of D-aspartic acid to total aspartic acid was in the range of 43.0 to 49.1%. The crude extracts of the hyperthermophiles exhibited aspartate racemase activity at 70 degrees C, and aspartate racemase homologous genes in them were identified by PCR. D-Enantiomers of other amino acids (alanine, leucine, phenylalanine, and lysine) in Thermococcus strains were also detected. Some of them might be by-products of aspartate racemase. It is proven that D-amino acids are produced in some hyperthermophilic archaea, although their function is unknown.

SUBMITTER: Matsumoto M

PROVIDER: S-EPMC103798 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature

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Occurrence of free D-amino acids and aspartate racemases in hyperthermophilic archaea.

Matsumoto M M Homma H H Long Z Z Imai K K Iida T T Maruyama T T Aikawa Y Y Endo I I Yohda M M

Journal of bacteriology 19991001 20

The occurrence of free D-amino acids and aspartate racemases in several hyperthermophilic archaea was investigated. Aspartic acid in all the hyperthermophilic archaea was highly racemized. The ratio of D-aspartic acid to total aspartic acid was in the range of 43.0 to 49.1%. The crude extracts of the hyperthermophiles exhibited aspartate racemase activity at 70 degrees C, and aspartate racemase homologous genes in them were identified by PCR. D-Enantiomers of other amino acids (alanine, leucine, ...[more]

PMID: 10515953

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