Disease relevance of purH

• The E. coli purH gene, therefore, specifies bifunctional 5'-phosphoribosyl 5-aminoimidazole-4-carboxamide transformylase-IMP cyclohydrolase [1].
• The plasmids carrying ORF-1 complemented not only the mutant cells defective in purH of E. coli but also the cells of Salmonella typhimurium lacking the activity of IMP cyclohydrolase (EC 3.5.4.10) which catalyzes the conversion of 5'-phosphoribosyl 5-formylaminoimidazole-4-carboxamide to IMP [1].
• The deduced amino acid sequence is 36% identical to the bacterial purH-encoded enzymes from Bacillus subtilis and E. coli [2].

High impact information on purH

• Both purH and purD genes constitute a single operon and are coregulated in expression by purines as other purine genes are [1].
• Nucleotide sequence analysis of genes purH and purD involved in the de novo purine nucleotide biosynthesis of Escherichia coli [1].

Biological context of purH

• The DNA sequence, maxicell and complementation analyses all supported the concept that the Mr 57,335 polypeptide is the product of the purH gene and encodes a bifunctional protein containing both AICAR transformylase and IMP cyclohydrolase activities [3].

Associations of purH with chemical compounds

• The operon was repressed in purH strains [5'-phosphoribosyl-5-amino-4-imidazolecarboxamide (AICAR)-accumulating] grown with limiting guanine or hypoxanthine, but derepressed by growth with limiting adenine [4].

References