Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Purification and characterization of human brain prolyl endopeptidase.

ABSTRACT: Prolyl endopeptidase (EC 3.4.21.26) was purified from human brain by a series of column-chromatographic steps using DEAE-cellulose DE-52, hydroxyapatite, phenyl-Sepharose, Sephacryl S-200 and f.p.l.c. (Mono Q). The enzyme was purified by a factor of 943 and was homogeneous in a SDS/polyacrylamide gel as judged by Coomassie Blue staining. The Mr estimated by SDS/PAGE is 79,600, and under native conditions on Sephacryl S-200 it is 85,600. Therefore the enzyme exists as a monomer. With benzyloxycarbonylglycylproline p-nitroanilide as substrate, the optimum pH of the enzyme is 6.8, and with the substrate concentration between 0.059 mM and 0.37 mM the Km is 9.0 x 10(-4) M. The pI of the enzyme is 4.75. The enzyme is classified as a serine proteinase, as it is strongly inhibited by di-isopropyl fluorophosphate. However, other serine proteinase inhibitors do not inhibit the enzyme significantly, suggesting that the active site of prolyl endopeptidase differs from that of classical serine proteinases such as trypsin. Polyclonal antibodies were raised against purified human brain prolyl endopeptidase in rabbits. Western-blot analysis, enzyme-inhibition assays, antibody binding and immunoprecipitation experiments indicated that the polyclonal antibodies are both specific and inhibitory to the enzyme activity.

SUBMITTER: Kalwant S

PROVIDER: S-EPMC1151170 | biostudies-other | 1991 May

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Similar Datasets

Induced-fit mechanism for prolyl endopeptidase.

Project description:Prolyl peptidases cleave proteins at proline residues and are of importance for cancer, neurological function, and type II diabetes. Prolyl endopeptidase (PEP) cleaves neuropeptides and is a drug target for neuropsychiatric diseases such as post-traumatic stress disorder, depression, and schizophrenia. Previous structural analyses showing little differences between native and substrate-bound structures have suggested a lock-and-key catalytic mechanism. We now directly demonstrate from seven structures of Aeromonus punctata PEP that the mechanism is instead induced fit: the native enzyme exists in a conformationally flexible opened state with a large interdomain opening between the beta-propeller and alpha/beta-hydrolase domains; addition of substrate to preformed native crystals induces a large scale conformational change into a closed state with induced-fit adjustments of the active site, and inhibition of this conformational change prevents substrate binding. Absolute sequence conservation among 28 orthologs of residues at the active site and critical residues at the interdomain interface indicates that this mechanism is conserved in all PEPs. This finding has immediate implications for the use of conformationally targeted drug design to improve specificity of inhibition against this family of proline-specific serine proteases.

| S-EPMC2898448 | biostudies-literature

Peptidomics of prolyl endopeptidase in the central nervous system.

Project description:Prolyl endopeptidase (Prep) is a member of the prolyl peptidase family and is of interest because of its unique biochemistry and connections to cognitive function. Using an unbiased mass spectrometry (MS)-based peptidomics platform, we identified Prep-regulated peptides in the central nervous system (CNS) of mice by measuring changes in the peptidome as a function of Prep activity. This approach was validated by the identification of known Prep substrates, such as the neuropeptide substance P and thymosin-beta4, the precursor to the bioactive peptide Ac-SDKP. In addition to these known substrates, we also discovered that Prep regulates many additional peptides, including additional bioactive peptides and proline rich peptides (PRPs). Biochemical experiments confirmed that some of these Prep-regulated peptides are indeed substrates of the enzyme. Moreover, these experiments also supported the known preference of Prep for shorter peptides while revealing a previously unknown cleavage site specificity of Prep when processing certain multi-proline-containing peptides, including PRPs. The discovery of Prep-regulated peptides implicates Prep in new biological pathways and provides insights into the biochemistry of this enzyme.

| S-EPMC2813186 | biostudies-literature

Prolyl Endopeptidase-like Deficiency Associated with Growth Hormone Deficiency

Project description:Prolyl endopeptidase-like (PREPL) deficiency (MIM#616224) is a rare congenital disorder characterised by neonatal hypotonia and feeding difficulties, growth hormone (GH) deficiency and hypergonadotropic hypogonadism. This syndrome is an autosomal recessive disease resulting from mutations in the PREPL gene (MIM#609557). Herein we report a 7-year-old female patient with biallelic mutations in PREPL (c.1528C>T in one allele and whole gene deletion in the other) with early growth impairment in infancy. GH deficiency was confirmed at 20 months of life. Recombinant GH treatment was introduced with a good response. Her clinical features were similar to those of previously reported cases. The description of new patients with PREPL deficiency syndrome is essential to better delineate the phenotypic and genotypic spectrum of the disease.

| S-EPMC10234053 | biostudies-literature

Maternal influence of prolyl endopeptidase on fat mass of adult progeny.

Project description:Maternal genotype has lifetime effects on progeny, but few specific genes, and no proteases, are known to underlie maternal effects. Prolyl endopeptidase (PREP) is a serine protease with putative substrates that regulate appetite or milk production.To test effects of PREP on obesity phenotypes in mice.Mice with a gene trap (GT) of PREP (PREP(gt/gt)) on the C57BL/6J (B6) background were generated. Minimal PREP protein was detected by western blot. In Experiment 1, direct effects of PREP were measured in littermate mice derived from intercrosses of heterozygotes (PREP(WT/gt)). In Experiment 2, maternal effects of PREP were measured in reciprocal crosses of heterozygous (PREP(WT/gt)) and wild-type (WT) (PREP(WT/WT)) males and females. DIETS: Mice were fed either low-fat (LF, Experiments 1 and 2) or high-fat (HF, Experiment 1) defined diets.Adiposity index (AI) was calculated from body weight (BW) and weights of four fat depots measured in 120-day-old mice. Fasting plasma glucose, insulin and leptin were measured. In vivo plasma alpha-MSH levels were measured by targeted quantitative peptidomics.Experiment 1-In intercross mice, there were significant diet effects, but few genotype effects. There were no genotype effects on BW or AI in males or females on either diet. Experiment 2-In contrast, reciprocal crosses of heterozygous males or females with WT B6 revealed highly significant parent of origin effects on all traits except body length. Progeny (WT and heterozygous genotypes and both sexes) born to female PREP(WT/gt) heterozygotes had fat pads that weighed as much as -twofold more at 120 days old than progeny born to male heterozygotes.Heterozygosity for PREP GT results in highly significant maternal effects, whereas homozygosity for the PREP(gt/gt) mutation has a much more limited direct effect.

| S-EPMC2743752 | biostudies-literature

Hypothalamic prolyl endopeptidase (PREP) regulates pancreatic insulin and glucagon secretion in mice.

Project description:Prolyl endopeptidase (PREP) has been implicated in neuronal functions. Here we report that hypothalamic PREP is predominantly expressed in the ventromedial nucleus (VMH), where it regulates glucose-induced neuronal activation. PREP knockdown mice (Prep(gt/gt)) exhibited glucose intolerance, decreased fasting insulin, increased fasting glucagon levels, and reduced glucose-induced insulin secretion compared with wild-type controls. Consistent with this, central infusion of a specific PREP inhibitor, S17092, impaired glucose tolerance and decreased insulin levels in wild-type mice. Arguing further for a central mode of action of PREP, isolated pancreatic islets showed no difference in glucose-induced insulin release between Prep(gt/gt) and wild-type mice. Furthermore, hyperinsulinemic euglycemic clamp studies showed no difference between Prep(gt/gt) and wild-type control mice. Central PREP regulation of insulin and glucagon secretion appears to be mediated by the autonomic nervous system because Prep(gt/gt) mice have elevated sympathetic outflow and norepinephrine levels in the pancreas, and propranolol treatment reversed glucose intolerance in these mice. Finally, re-expression of PREP by bilateral VMH injection of adeno-associated virus-PREP reversed the glucose-intolerant phenotype of the Prep(gt/gt) mice. Taken together, our results unmask a previously unknown player in central regulation of glucose metabolism and pancreatic function.

| S-EPMC4136568 | biostudies-literature

Prolyl endopeptidase contributes to early neutrophilic inflammation in acute myocardial transplant rejection.

Project description:Altered inflammation and tissue remodeling are cardinal features of cardiovascular disease and cardiac transplant rejection. Neutrophils have increasingly been understood to play a critical role in acute rejection and early allograft failure; however, discrete mechanisms that drive this damage remain poorly understood. Herein, we demonstrate that early acute cardiac rejection increases allograft prolyl endopeptidase (PE) in association with de novo production of the neutrophil proinflammatory matrikine proline-glycine-proline (PGP). In a heterotopic murine heart transplant model, PGP production and PE activity were associated with early neutrophil allograft invasion and allograft failure. Pharmacologic inhibition of PE with Z-Pro-prolinal reduced PGP, attenuated early neutrophil graft invasion, and reduced proinflammatory cytokine expression. Importantly, these changes helped preserve allograft rejection-free survival and function. Notably, within 2 independent patient cohorts, both PGP and PE activity were increased among patients with biopsy-proven rejection. The observed induction of PE and matrikine generation provide a link between neutrophilic inflammation and cardiovascular injury, represent a potential target to reduce allogenic immune responses, and uncover a mechanism of cardiovascular disease that has been previously unrecognized to our knowledge.

| S-EPMC8026194 | biostudies-literature

Generation of food-grade recombinant Lactobacillus casei delivering Myxococcus xanthus prolyl endopeptidase.

Project description:Prolyl endopeptidases (PEP) (EC 3.4.21.26), a family of serine proteases with the ability to hydrolyze the peptide bond on the carboxyl side of an internal proline residue, are able to degrade immunotoxic peptides responsible for celiac disease (CD), such as a 33-residue gluten peptide (33-mer). Oral administration of PEP has been suggested as a potential therapeutic approach for CD, although delivery of the enzyme to the small intestine requires intrinsic gastric stability or advanced formulation technologies. We have engineered two food-grade Lactobacillus casei strains to deliver PEP in an in vitro model of small intestine environment. One strain secretes PEP into the extracellular medium, whereas the other retains PEP in the intracellular environment. The strain that secretes PEP into the extracellular medium is the most effective to degrade the 33-mer and is resistant to simulated gastrointestinal stress. Our results suggest that in the future, after more studies and clinical trials, an engineered food-grade Lactobacillus strain may be useful as a vector for in situ production of PEP in the upper small intestine of CD patients.

| S-EPMC4393947 | biostudies-literature

Slow tight-binding inhibition of prolyl endopeptidase by benzyloxycarbonyl-prolyl-prolinal.

Project description:Prolyl endopeptidase is a serine proteinase that specifically cleaves peptides on the carboxy side of proline residues. Wilk & Orlowski [(1983) J. Neurochem. 41, 69-75] have shown that benzyloxycarbonyl-prolyl-prolinal (Z-prolyl-prolinal) is a potent inhibitor of prolyl endopeptidase. We show that Z-prolyl-prolinal is a slow-binding inhibitor of mouse brain prolyl endopeptidase with Ki 0.35 +/- 0.05 nM. Kinetic analysis indicates that the mechanism is a simple, but slow, reversible equilibrium between free and bound enzyme (E + I in equilibrium EI) with rate constants for association (kon) and dissociation (koff) of 1.6 X 10(5) M-1.s-1 and approx. 4 X 10(-5) s-1 respectively. Slow-binding inhibition is dependent on the presence of the aldehyde group since the alcohol (Z-prolyl-prolinol) is a rapid and 50,000-fold poorer inhibitor (Ki 19 microM). Prolyl endopeptidase from human brain is also inhibited by Z-prolyl-prolinal with kinetics similar to those of the mouse brain enzyme.

| S-EPMC1149592 | biostudies-other

Prolyl endopeptidase-like is a (thio)esterase involved in mitochondrial respiratory chain function.

Project description:Deficiency of the serine hydrolase prolyl endopeptidase-like (PREPL) causes a recessive metabolic disorder characterized by neonatal hypotonia, feeding difficulties, and growth hormone deficiency. The pathophysiology of PREPL deficiency and the physiological substrates of PREPL remain largely unknown. In this study, we connect PREPL with mitochondrial gene expression and oxidative phosphorylation by analyzing its protein interactors. We demonstrate that the long PREPLL isoform localizes to mitochondria, whereas PREPLS remains cytosolic. Prepl KO mice showed reduced mitochondrial complex activities and disrupted mitochondrial gene expression. Furthermore, mitochondrial ultrastructure was abnormal in a PREPL-deficient patient and Prepl KO mice. In addition, we reveal that PREPL has (thio)esterase activity and inhibition of PREPL by Palmostatin M suggests a depalmitoylating function. We subsequently determined the crystal structure of PREPL, thereby providing insight into the mechanism of action. Taken together, PREPL is a (thio)esterase rather than a peptidase and PREPLL is involved in mitochondrial homeostasis.

| S-EPMC8634043 | biostudies-literature