Patent ID: 6184020
Filing Date: 2001-02-06
Classification: A23J,C12N,C12P

Abstract:
An isolated polypeptide having aminopeptidase activity obtained from a Sphingomonas strain, selected from the group consisting of:(a) a polypeptide having an amino acid sequence which has at least 95% identify with amino acids 33 to 674 of SEQ ID NO:2;(b) a polypeptide which is encoded by a nucleic acid sequence which hybridizes under medium stringency conditions with (i) nucleotides 670 to 2592 of SEQ ID NO:1, (ii) its complementary strand; or (iii) a fragment consisting of at least 100 contiguous nucleotides of nucleotides 670 to 2592 of SEQ ID NO:1, wherein medium stringency conditions are defined as prehybridization and hybridization at 42.degree. c. in 5.times. SSPE, 0.3% SDS, 200 .mu.g/ml sheared and denatured salmon sperm DNA, and 35% formamide, and washing with 2.times. SSC, 0.2% SDS at 55.degree. C.(c) an enzymatically active fragment of (a) or (b); and(d) a polypeptide which (i) has aminopeptidase activity in the pH range between pH 5.0-8.5 measured at 37.degree. C., (ii) has an isoelectric point in the range of 7.4-8.5; (iii) has aminopeptidase activity in the temperature range of 20-55.degree. C., measured at pH 7.5 using Gly-para-nitroanilide in Tris-HCl buffer; (iv) hydrolyzes ala-para-nitroanilide, Gly-para-nitroanilide, Leu-para-nitroanilide, Glu-para-nitroanilide, Asp-para-nitroanilide, Lys-para-nitroanilide or Pro-para-nitroanilide; (iv) is not inhibited by phenylmethanesulfonyl fluoride; and (iv) has a molecular mass of 67 .+-.5 kDa by SDS-PAGE.