Disease relevance of dadX

• Organization and expression of the Escherichia coli K-12 dad operon encoding the smaller subunit of D-amino acid dehydrogenase and the catabolic alanine racemase [1].
• The predicted dadX gene product appeared to be 85% identical to a dadB-encoded catabolic alanine racemase of Salmonella typhimurium [1].
• Alanine racemase from Helicobacter pylori NCTC 11637:Purification, characterization and gene cloning [2].
• Expression of alr gene from Corynebacterium glutamicum ATCC 13032 in Escherichia coli and molecular characterization of the recombinant alanine racemase [3].
• Alanine racemase from the acidophile Acetobacter aceti [4].

High impact information on dadX

• A comparison of the amino acid sequence with those of Bacillus subtilis and Salmonella typhimurium dadB and alr enzymes revealed overall sequence homologies of 31-54%, including an identical octapeptide bearing the pyridoxal 5'-phosphate binding site [5].
• The operon has a high similarity to the dadAB operon of Salmonella typhimurium and the dadAX operon of Escherichia coli, each of which codes for the smaller subunit of D-amino acid dehydrogenase and the catabolic alanine racemase [6].
• Knockout of the alr gene abolished all measurable alanine racemase activity, and the mutant was shown to be strictly dependent on D-alanine for growth [7].
• A fragment of the Escherichia coli K-12 chromosome complementing the D-amino acid dehydrogenase and catabolic alanine racemase deficiency of a dad operon deletion mutant was cloned in a mini-Mu plasmid [1].
• A psychrophilic alanine racemase gene from Bacillus psychrosaccharolyticus was cloned and expressed in Escherichia coli SOLR with a plasmid pYOK3 [8].

Associations of dadX with chemical compounds

• Alanine racemase (Alr) is a pyridoxal 5' phosphate (PLP) -dependent enzyme that catalyzes the interconversion of the d- and l-isomers of alanine and has a basic pH optimum [4].

References