Open AccessCold‐sensitive growth and decreased GTP‐hydrolytic activity from substitution of Pro17 for Val in Era, an essential Escherichia coli GTPase
Author(s) -
Lerner Claude G.,
Sood Poonam,
Ahnn Joohong,
Inouye Masayori
Publication year - 1992
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1992.tb05356.x
Subject(s) - gtp' , gtpase , mutant , mutation , biology , guanine , small gtpase , microbiology and biotechnology , biochemistry , nucleotide , mutant protein , guanine nucleotide exchange factor , chemistry , enzyme , gene , signal transduction
A substitution mutation of Pro17 by Val (P17V) was constructed in the guanine nucleotide binding domain of Era, an essential protein in Escherichia coli . The mutation is analogous to the oncogenic activating allele at position 12 in the GTP‐binding domain of p21 ras . The phenotype of this mutant was analysed in a strain which exclusively expressed the mutant protein (Era‐V17) in null allele chromosomal background ( era1::kan ). The strain was found to be cold‐sensitive for growth. Mutant Era‐V17 purified from the strain was cold‐sensitive for GTP‐hydrolytic activity, suggesting that the GTPase activity of Era is required for cell growth since the P17V mutation resulted in both cold‐sensitive growth of cells and cold‐labile GTPase activity of the purified protein.