Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.16.2 (PCP)
 3,761 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After gel filtration the supernatant of Triton X-100 treated membrane sediments of Acinetobacter calcoaceticus shows activities for alanyl aminopeptidase, leucyl aminopeptidase, glutamyl aminopeptidase, prolyl aminopeptidase, aminopeptidase My, gamma-glutamyl arylamidase, dipeptidylpeptidase IV and prolyl carboxypeptidase. The intracellular localization of the enzymes was analyzed by sucrose density gradient centrifugation of the DNase/RNase pretreated membrane sediments. Most of the exopeptidases are located in the inner membrane fractions (band L). Only gamma-glutamyl arylamidase is located with its main activity in the cytoplasmic membrane (band M). Only small exopeptidase activities could be found in the outer membrane (band H).
 ...
PMID:[Identification and localization of exopeptidase activities bound to membranes of Acinetobacter calcoaceticus]. 269 71

A proline dipeptidase (EC 3.4.13.9) from guinea pig brain was purified to over 90% homogeneity by a combination of ammonium sulfate fractionation, DEAE-cellulose chromatography, calcium phosphate-cellulose chromatography, chromatofocusing, and gel filtration on Sephadex G-200. A purification factor of 2718-fold was obtained with a yield of 7%. The purified enzyme was found to have an apparent molecular weight of 132,000 and to consist of two dissimilar subunits of molecular weights 64,000 and 68,000. The substrate specificity of the enzyme is not that of a strict proline dipeptidase. Although it preferentially hydrolyzes proline dipeptides (Leu-Pro) it also hydrolyzes prolyl dipeptides (Pro-Leu) and dipeptides not containing proline (Leu-Leu). The purified enzyme preparation exhibited weak aminoacylproline aminopeptidase activity against Arg-Pro-Pro but it did not exhibit any post-proline dipeptidyl aminopeptidase, post-proline cleaving endopeptidase, proline iminopeptidase, prolyl carboxypeptidase or carboxypeptidase P activities when tested with a large variety of peptides and arylamides. With all of the proline and prolyl dipeptides examined the enzyme exhibited biphasic kinetics (two distinct slopes on Lineweaver-Burk plots). However, with Leu-Leu as substrate normal Michaelis-Menten kinetics were obeyed.
 ...
PMID:The purification and characterization of a proline dipeptidase from guinea pig brain. 685 81

Peptidases which are specific for proline residues have been described and include endopeptidases (post-proline cleaving enzyme and proline specific endopeptidase), N-terminal exopeptidases (post-proline dipeptidyl aminopeptidase, proline iminopeptidase, aminopeptidase P), C-terminal exopeptidases (prolylcarboxypeptidase, and carboxypeptidase P) and dipeptidases (prolyl dipeptidase and proline dipeptidase). The properties, distinguishing charcteristics, and possible significance of these proline specific endo- and exopeptidases are discussed. In addition, reference is made to a series of enzymes which can hydrolyze proline containing peptide bonds, but which are not specific for proline.
 ...
PMID:Proline specific endo- and exopeptidases. 699 12

In spite of the numerous studies regarding prolyl aminopeptidase, little is known about its mechanism and the significance of its similarity to a number of hydrolases of diverse specificity that belong to the alpha/beta hydrolase-fold family (Pseudomonas 2-hydroxymuconic semialdehyde hydrolase, atropinesterase, and 2-hydroxy-6-oxophenylhexa-2,4-dienoic acid hydrolase; human and rat epoxide hydrolases). We report the cloning and sequencing of the novel prolyl aminopeptidase gene from Flavobacterium meningosepticum (FPAP) which allowed a more comprehensive sequence comparison. FPAP was found to be a 35-kDa monomeric enzyme, releasing N-terminal proline but not hydroxyproline residues from small peptides and naphthylamide esters. Using the unweighted pair group method with arithmetic mean method, an evolutionary tree that depicts the probable relationship between the prolyl aminopeptidases and the alpha/beta hydrolase-fold enzymes was constructed. Since the alpha/beta hydrolase-fold family might also include the members of the prolyl oligopeptidase family (prolyl oligopeptidase, dipeptidyl peptidase IV, and prolyl carboxypeptidase), this proposal links all the known Pro-Y bond-cleaving proline-specific peptidases (prolyl oligopeptidase family, prolyl aminopeptidases, and prolinase) as enzymes with similar scaffolds and hydrolytic mechanisms. On the other hand, the enzymes that cleave X-Pro bonds are metalloenzymes grouped within the "pita-bread" fold family (aminopeptidase P and prolidase). Although the latter two enzymes show significant sequence homology, prolyl aminopeptidase, prolinase, and the members of the prolyl oligopeptidase family do not, and might share the alpha/beta hydrolase-fold scaffold. This rationale would explain the failure in finding a common "proline-recognizing motif" in the primary structures of these proline-specific peptidases.
 ...
PMID:Prolyl aminopeptidase gene from Flavobacterium meningosepticum: cloning, purification of the expressed enzyme, and analysis of its sequence. 895 Oct 32

Various food proteins including, e.g. gluten, collagen and casein are rich in L-proline residues. Due to the cyclic structure of proline, these proteins are well protected from enzymatic degradation by typical digestive enzymes. Proline-specific peptidases (PsP) belong to different families of hydrolases acting on peptide bonds (EC 3.4.x.x). They occur in various organisms including bacteria, fungi, plants and insects. Based on their biochemical characteristics, PsP type enzymes are further grouped into different subclasses of which prolyl aminopeptidases (EC 3.4.11.5, PAP), prolyl carboxypeptidases (EC 3.4.17.16, PCP) and prolyl oligopeptidases/prolyl endopeptidases (EC 3.4.21.26, POP/PEP) are of major interest for applications in food biotechnology. This mini review summarises the biochemical assays employed for these subclasses of PsP and their structural properties and the reaction mechanisms. A special focus was set on PsP derived from fungi and insects and important industrial applications in the field of food biotechnology. The degradation of gluten and collagen as well as the hydrolysis of bitter peptides are discussed.
...
PMID:Prolyl-specific peptidases for applications in food protein hydrolysis. 2623 67