Open AccessThe Escherichia coli dnaJ mutation affects biosynthesis of specific proteins, including those of the lac operon
Author(s) -
Masafumi Ohki,
Hidenobu Uchida,
Fumie Tamura,
Reiko Ohki,
Susumu Nishimura
Publication year - 1987
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.169.5.1917-1922.1987
Subject(s) - biology , mutant , dnaa , escherichia coli , operon , dnab helicase , protein biosynthesis , biochemistry , lac operon , mutation , dna synthesis , dna , dna replication , microbiology and biotechnology , gene , rna , origin of replication , helicase
Temperature-sensitive dnaJ mutants of Escherichia coli showed a thermosensitive defect in the synthesis of beta-galactosidase. Synthesis of the lac mRNA was greatly reduced at the restrictive temperature. The mutants were also conditionally defective in the synthesis of a subset of membrane proteins such as succinate dehydrogenase, whereas the synthesis of anthranilate synthetase, encoded by trpED, as well as that of most cellular proteins, was unaffected at the restrictive temperature. The defect was specific for the dnaJ mutants among several dna mutants which are known to be involved in the initiation of DNA synthesis: dnaK, dnaA, and dnaB mutants synthesized each of these proteins normally even at the restrictive temperature. At the restrictive temperature, growth of the dnaJ mutants was arrested at a specific stage of the cell cycle.