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Disulfide engineering at the dimer interface of Lactobacillus casei thymidylate synthase: crystal structure of the T155C/E188C/C244T mutant.

ABSTRACT: The crystal structure of a covalently cross-linked Lactobacillus casei thymidylate synthase has been determined at 2.8 A resolution. The sites for mutation to achieve the bis-disulfide linked dimer were identified using the disulfide modeling program MODIP. The mutant so obtained was found to be remarkably thermostable. This increase in stability has been reasoned to be entirely a consequence of the covalent gluing between the two subunits.

SUBMITTER: Velanker SS

PROVIDER: S-EPMC2144305 | biostudies-other | 1999 Apr

REPOSITORIES: biostudies-other

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Disulfide engineering at the dimer interface of Lactobacillus casei thymidylate synthase: crystal structure of the T155C/E188C/C244T mutant.

Velanker S S SS Gokhale R S RS Ray S S SS Gopal B B Parthasarathy S S Santi D V DV Balaram P P Murthy M R MR

Protein science : a publication of the Protein Society 19990401 4

The crystal structure of a covalently cross-linked Lactobacillus casei thymidylate synthase has been determined at 2.8 A resolution. The sites for mutation to achieve the bis-disulfide linked dimer were identified using the disulfide modeling program MODIP. The mutant so obtained was found to be remarkably thermostable. This increase in stability has been reasoned to be entirely a consequence of the covalent gluing between the two subunits. ...[more]

PMID: 10211840

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