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Improvement of crystal quality by surface mutations of beta-lactamase Toho-1.

ABSTRACT: The beta-lactamase Toho-1 exhibits a strong tendency to form merohedrally twinned crystals. Here, the crystal quality of Toho-1 was improved by using surface modification to remove a sulfate ion involved in crystal packing. The surface-modified Toho-1 variant (R274N/R276N) was crystallized under similar conditions to those used for wild-type Toho-1. R274N/R276N did not form merohedrally twinned crystals. The crystals diffracted to a significantly higher resolution (approximately 0.97 A) than the wild-type crystals (1.65 A); they belonged to the same space group and had almost identical unit-cell parameters to those of wild-type Toho-1.

SUBMITTER: Shimamura T

PROVIDER: S-EPMC2664765 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Improvement of crystal quality by surface mutations of beta-lactamase Toho-1.

Shimamura Tatsuro T Nitanai Yasushi Y Uchiyama Takuro T Matsuzawa Hiroshi H

Acta crystallographica. Section F, Structural biology and crystallization communications 20090325 Pt 4

The beta-lactamase Toho-1 exhibits a strong tendency to form merohedrally twinned crystals. Here, the crystal quality of Toho-1 was improved by using surface modification to remove a sulfate ion involved in crystal packing. The surface-modified Toho-1 variant (R274N/R276N) was crystallized under similar conditions to those used for wild-type Toho-1. R274N/R276N did not form merohedrally twinned crystals. The crystals diffracted to a significantly higher resolution (approximately 0.97 A) than the ...[more]

PMID: 19342785

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