The N-terminal domain of the Caulobacter crescentus CgtA protein does not function as a guanine nucleotide exchange factor

B Lin; J R Maddock

doi:10.1016/s0014-5793(00)02402-9

The N-terminal domain of the Caulobacter crescentus CgtA protein does not function as a guanine nucleotide exchange factor

FEBS Lett. 2001 Jan 26;489(1):108-11. doi: 10.1016/s0014-5793(00)02402-9.

Authors

B Lin¹, J R Maddock

Affiliation

¹ Department of Biology, University of Michigan, 830 N University, Ann Arbor, MI 48109-1048, USA.

PMID: 11231024
DOI: 10.1016/s0014-5793(00)02402-9

Abstract

The Caulobacter crescentus GTP binding protein CgtA is a member of the Obg/GTP1 subfamily of monomeric GTP binding proteins. In vitro, CgtA displays moderate affinity for both GDP and GTP, and rapid exchange rate constants for either nucleotide. One possible explanation for the observed rapid guanine nucleotide exchange rates is that CgtA is a bimodal protein with a C-terminal GTP binding domain and an N-terminal guanine nucleotide exchange factor (GEF) domain. In this study we demonstrate that although the N-terminus of CgtA is required for function in vivo, this domain plays no significant role in the guanine nucleotide binding, exchange or GTPase activity.

MeSH terms

Alleles
Bacterial Proteins*
Caulobacter crescentus / genetics
Caulobacter crescentus / metabolism*
GTP Phosphohydrolases / metabolism
Guanine Nucleotide Exchange Factors / chemistry
Guanine Nucleotide Exchange Factors / metabolism*
Guanine Nucleotides / metabolism*
Guanosine Triphosphate / metabolism
Hydrolysis
Monomeric GTP-Binding Proteins / chemistry
Monomeric GTP-Binding Proteins / genetics
Monomeric GTP-Binding Proteins / metabolism*
Protein Structure, Tertiary

Substances

Bacterial Proteins
Guanine Nucleotide Exchange Factors
Guanine Nucleotides
Guanosine Triphosphate
CgtA protein, bacteria
GTP Phosphohydrolases
Monomeric GTP-Binding Proteins