Alkaline D-peptidase

A Japanese Screening Approach Selection of an Opine Dehydrogenase and Alkaline D-Peptidase... 

In this paper, enrichment and acclimation techniques are introduced with the isolation of nitrile degraders as typical examples. Furthermore, two recent examples of microbial screening by the use of synthetic substrates for opine dehydrogenase and alkaline D-peptidase are described. 

Few microbial proteases acting on n-peptides are known. The alkaline D-peptidase (ADP) from Bacillus cereus is related to Du-carboxypeptidase and p-lactamases. These enz unes have an accessible groove in which the nucleophilic serine and other catalytic amino acids are located. This n-peptidase could be applied for the synthesis of the 92-amino acid peptidyl prolyl cis-trans isomerase from Escherichia coli by condensation of two peptide fragments, of which the 35-amino acid acyl donor was activated as the OGp ester [62]. Thus the D-amino acid-selective enzyme was used for preparing a protein composed of L-amino acids and making the product insensitive to hydrolysis by the coupling enzyme. 

Alkaline D-peptidase (ADP) Bacillus cereus DF4-B Ser Peptide bond formation... 

Discovery of D-Aminopeptidase, D-Amino Acid Amidase, and Alkaline o-Peptidase... 

Since o-stereospecific amino acid amides and peptide hydrolases were previously unknown and were not targets of enz3unology, we started to screen for these enzymes and subsequently discovered three kinds that exhibited D-stereoselectivities for o-amino acid derivatives o-aminopeptidase [4], o-amino acid amidase [5], and alkaline o-peptidase [6] (Table 19.1). Ochrobactrum anthropi Cl-38 was isolated through an enridiment culture technique as a utilizer of o-alanine amide (o-Ala-NH ) as the sole... 

Ochrobactrum anthropi SV3 was isolated as a D-valine amide degrader after a 4-month acclimation of bacterial culture. The strain produced an enzyme that was characterized as o-amino acid amidase (DaaA) [5], Furthermore, Bacillus cereus DF4-B excreted alkaline o-peptidase (ADP), which acted on the synthehc oligopeptide D-phenylalanine tetramer (o-Phe). The enzyme was characterized as the first endopeptidase acting on D-amino acid-containing peptides by recognizing the second amino acid from its N-terminus under alkaline conditions [6]. 

Figure 10 Schematics of three-metal cocatalytic sites (a) represented by E. coli alkaline phosphatase/ and two-metal cocatalytic sites (b) represented by Aeromonas proteolytic amino peptidase/ The one-letter codes D, E, and H are given for the amino acids Asp, Glu, and His respectively...

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