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Sequencing and expression of additional xylanase genes from the hyperthermophile Thermotoga maritima FjSS3B.1.

ABSTRACT: Two genes, xynB and xynC, coding for xylanases were isolated from Thermotoga maritima FjSS3B.1 by a genomic-walking-PCR technique. Sequencing of the genes showed that they encode multidomain family 10 xylanases. Only XynB exhibited activity against xylan substrates. The temperature optimum (87 degrees C) and pH optimum (pH 6.5) of XynB are different from the previously reported xylanase, XynA (also a family 10 enzyme), from this organism. The catalytic domain expressed without other domains has a lower temperature optimum, is less thermostable, and has optimal activity at pH 6.5. Despite having a high level of sequence similarity to xynB, xynC appears to be nonfunctional since its encoded protein did not show significant activity on xylan substrates.

SUBMITTER: Reeves RA

PROVIDER: S-EPMC92019 | biostudies-literature | 2000 Apr

REPOSITORIES: biostudies-literature

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Sequencing and expression of additional xylanase genes from the hyperthermophile Thermotoga maritima FjSS3B.1.

Reeves R A RA Gibbs M D MD Morris D D DD Griffiths K R KR Saul D J DJ Bergquist P L PL

Applied and environmental microbiology 20000401 4

Two genes, xynB and xynC, coding for xylanases were isolated from Thermotoga maritima FjSS3B.1 by a genomic-walking-PCR technique. Sequencing of the genes showed that they encode multidomain family 10 xylanases. Only XynB exhibited activity against xylan substrates. The temperature optimum (87 degrees C) and pH optimum (pH 6.5) of XynB are different from the previously reported xylanase, XynA (also a family 10 enzyme), from this organism. The catalytic domain expressed without other domains has ...[more]

PMID: 10742238

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(Beta alpha)8-barrel proteins of tryptophan biosynthesis in the hyperthermophile Thermotoga maritima.

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Partial characterization of the Streptomyces lividans xlnB promoter and its use for expression of a thermostable xylanase from Thermotoga maritima.

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