PMID:21992469

Citation	Landmann, JJ, Busse, RA, Latz, JH, Singh, KD, Stülke, J and Görke, B (2011) Crh, the paralogue of the phosphocarrier protein HPr, controls the methylglyoxal bypass of glycolysis in Bacillus subtilis. Mol. Microbiol. 82:770-87
Abstract	The histidine protein HPr has a key role in regulation of carbohydrate utilization in low-GC Gram-positive bacteria. Bacilli possess the paralogue Crh. Like HPr, Crh becomes phosphorylated by kinase HPrK/P in response to high fructose-1,6-bisphosphate concentrations. However, Crh can only partially substitute for the regulatory functions of HPr leaving its role mysterious. Using protein co-purification, we identified enzyme methylglyoxal synthase MgsA as interaction partner of Crh in Bacillus subtilis. MgsA converts dihydroxyacetone-phosphate to methylglyoxal and thereby initiates a glycolytic bypass that prevents the deleterious accumulation of phospho-sugars under carbon overflow conditions. However, methylgyloxal is toxic and its production requires control. We show here that exclusively the non-phosphorylated form of Crh interacts with MgsA in vivo and inhibits MgsA activity in vitro. Accordingly, Crh inhibits methylglyoxal formation in vivo under nutritional famine conditions that favour a low HPr kinase activity. Thus, Crh senses the metabolic state of the cell, as reflected by its phosphorylation state, and accordingly controls flux through the harmful methylglyoxal pathway. Interestingly, HPr is unable to bind and regulate MgsA, making this a bona fide function of Crh. Four residues that differ in the interaction surfaces of HPr and Crh may account for this difference.
Links	PubMed Online version:10.1111/j.1365-2958.2011.07857.x
Keywords	Amino Acid Sequence; Bacillus subtilis/metabolism; Bacterial Proteins/metabolism; Dihydroxyacetone Phosphate/metabolism; Fructosediphosphates/metabolism; Glycolysis; Metabolic Networks and Pathways; Models, Biological; Molecular Sequence Data; Phosphoproteins/metabolism; Phosphorylation; Protein Interaction Mapping; Protein Kinases/metabolism; Pyruvaldehyde/metabolism; Sequence Homology, Amino Acid
edit table

Annotations

Gene product	Qualifier	GO Term	Evidence Code	with/from	Aspect	Extension	Notes	Status
BACSU:MGSA		GO:0008929: methylglyoxal synthase activity	ECO:0000314:		F		On page 777, the authors state that they performed direct assays where MgsA protein is incubated with its substrate, DHAP and methylglyoxal is produced. The methylglyoxal is said to have been measured spectrophotometrically.	complete CACAO 4697
BACSU:MGSA	enables	GO:0008929: methylglyoxal synthase activity	ECO:0000314: direct assay evidence used in manual assertion		F		Seeded From UniProt	complete

References

See Help:References for how to manage references in GONUTS.