Structural highlights
Function
[OBG_BACSU] Necessary for the transition from vegetative growth to stage 0 or stage II of sporulation, but sporulation subsequent to these stages is unaffected at 45 degrees Celsius. This ts effect is probably due solely to the E-79 mutation. Required for expression of early sporulation genes, further suggesting a role in the induction of sporulation. Depletion effects on sporulation can be partially suppressed by missense mutations in spo0A. Strains depleted for obg stop growing after about 3 hours and do not induce the sigma-B factor following ethanol stress. It cofractionates with the ribosome and upstream stress response regulators RsbR, RsbS and RsbT in size fractionation columns, suggesting the ribosome might serve as a possible mediator of the activity of obg and the stress induction of sigma-B. In glycerol gradients partially associates with ribosomes; this is stabilized by a nonhydrolyzable GTP-analog and to a lesser extent GTP and GDP.[1] [2]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
The Obg nucleotide binding protein family has been implicated in stress response, chromosome partitioning, replication initiation, mycelium development, and sporulation. Obg proteins are among a large group of GTP binding proteins conserved from bacteria to man. Members of the family contain two equally and highly conserved domains, a C-terminal GTP binding domain and an N-terminal glycine-rich domain. Structural analysis of Bacillus subtilis Obg revealed respective domain architectures and how they are coupled through the putative switch elements of the C-terminal GTPase domain in apo and nucleotide-bound configurations. Biochemical analysis of bacterial and human Obg proteins combined with the structural observation of the ppGpp nucleotide within the Obg active sight suggest a potential role for ppGpp modulation of Obg function in B. subtilis.
Structural and biochemical analysis of the Obg GTP binding protein.,Buglino J, Shen V, Hakimian P, Lima CD Structure. 2002 Nov;10(11):1581-92. PMID:12429099[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Vidwans SJ, Ireton K, Grossman AD. Possible role for the essential GTP-binding protein Obg in regulating the initiation of sporulation in Bacillus subtilis. J Bacteriol. 1995 Jun;177(11):3308-11. PMID:7768831
- ↑ Scott JM, Haldenwang WG. Obg, an essential GTP binding protein of Bacillus subtilis, is necessary for stress activation of transcription factor sigma(B). J Bacteriol. 1999 Aug;181(15):4653-60. PMID:10419966
- ↑ Buglino J, Shen V, Hakimian P, Lima CD. Structural and biochemical analysis of the Obg GTP binding protein. Structure. 2002 Nov;10(11):1581-92. PMID:12429099
