Characterization of stationary-phase proteins in Streptomyces coelicolor A3(2)

LELIA ORSARIA , LUCIANA PAOLETTI , HUGO C GRAMAJO

FEMS MICROBIOLOGY LETTERS

Elsevier

Lugar: Amsterdam; Año: 1998 vol. 162 p. 275 - 281

0378-1097

Using two-dimensional (2-D) gel electrophoresis, we have analyzed the continuous changes in protein profiles, from exponential to late stationary phase, of Streptomyces coelicolor cultures growing in liquid minimal medium. Six proteins were purified from 2-D gels and characterized by N-terminal sequencing. Three amino acid sequences showed a high percentage of identity with other known proteins. Two of them match with the iron/zinc-containing superoxide dismutase recently described in S. coelicolor and the third one with a tellurite resistance protein from Alcaligenes sp. The activities of the nickel-containing superoxide dismutase and the iron/zinc superoxide dismutase throughout growth were determined in native PAGE. Both activities reached their maximal levels after post-exponential growth. However, while the nickel superoxide dismutase reached its maximum during the early stationary phase, the iron/zinc superoxide dismutase peaked during late stationary phase.