Table 2.

Physicochemical properties of the CARB-6 β-lactamase ofV. cholerae and comparison with TEM-1 and other carbenicillin-hydrolyzing enzymes

β-LactamaseMol wtpIa
CARB-633,000b5.35
SAR-133,700b4.9
TEM-128,911c5.4
CARB-131,405c5.3
CARB-231,347c5.7
CARB-331,313c5.75
  • a pI was determined in a polyacrylamide gel with an Ampholine gradient (pH 3.5 to 9.5; Pharmacia).

  • b Molecular weight determined by electrophoresis in an SDS–12% polyacrylamide gel by the method of Laemmli (19) with low-range prestained SDS-polyacrylamide gel electrophoresis standards.

  • c Molecular weight as estimated according to the amino acid sequence. The molecular mass of CARB-6 calculated according to the amino acid composition is 31,429 Da (Bio-Oriented Web Server Facilities, ABIM-Aix Marseille University).