PRIMARY STRUCTURE OF N-ACYL-D-GLUTAMATE AMIDOHYDROLASE FROM ALCALIGENES XYLOSOXYDANS SUBSP XYLOSOXYDANS A-6

The gene coding the N-acyl-D-glutamate amidohydrolase of Alcaligenes x ylosoxydans subsp. xylosoxydans A-6 (Alcaligenes A-6) was cloned and i ts complete DNA sequence was determined. The N-acyl-D-glutamate amidoh ydrolase structural gene consists of 1,464 nucleotides and encodes 488 amino acid residues. The molecular weight of the enzyme was calculate d to be 51,490. This value is close to the apparent molecular weight o f 59,000 determined for the purified enzyme from Alcaligenes A-6 by so dium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE). The N-terminal amino acid sequence of the recombinant protein exactly matches the amino acid sequence derived from the DNA sequence and that determined from the Alcaligenes A-6 enzyme (NK2-MQEKLDLVIEGGWVIDGLGG) . The deduced amino acid sequence of the cloned N-acyl-D-glutamate ami dohydrolase showed high sequence homology with those of N-acyl-D-aspar tate amidohydrolase (46%) and D-aminoacylase (47%) from Alcaligenes A- 6. This fact strongly suggests that these three enzymes have evolved f rom a common ancestral gene.