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Role of aminotransferase IlvE in production of branched-chain fatty acids by Lactococcus lactis subsp. lactis.

ABSTRACT: The objective of this study was to determine the role of a lactococcal branched-chain amino acid aminotransferase gene, ilvE, in the production of branched-chain fatty acids. Lactococcus lactis subsp. lactis LM0230 and an ilvE deletion mutant, JLS450, produced branched-chain fatty acids from amino and alpha-keto acids at levels above alpha-keto acid spontaneous degradation and the fatty acids' flavor thresholds. The deletion mutant produced the same amounts of branched-chain fatty acids from precursor amino acids as did the parent. This was not the case, however, for the production of branched-chain fatty acids from the corresponding precursor alpha-keto acids. The deletion mutant produced a set of fatty acids different from that produced by the parent. We concluded from these observations that ilvE plays a role in the specific type of fatty acids produced but has little influence on the total amount of fatty acids produced by lactococci.

SUBMITTER: Ganesan B

PROVIDER: S-EPMC321303 | biostudies-literature | 2004 Jan

REPOSITORIES: biostudies-literature

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Role of aminotransferase IlvE in production of branched-chain fatty acids by Lactococcus lactis subsp. lactis.

Ganesan Balasubramanian B Weimer Bart C BC

Applied and environmental microbiology 20040101 1

The objective of this study was to determine the role of a lactococcal branched-chain amino acid aminotransferase gene, ilvE, in the production of branched-chain fatty acids. Lactococcus lactis subsp. lactis LM0230 and an ilvE deletion mutant, JLS450, produced branched-chain fatty acids from amino and alpha-keto acids at levels above alpha-keto acid spontaneous degradation and the fatty acids' flavor thresholds. The deletion mutant produced the same amounts of branched-chain fatty acids from pre ...[more]

PMID: 14711703

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