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Tannous R, Shelef O, Kopp T, Fridman M, Shabat D. Hyper-Responsive Chemiluminescent Probe Reveals Distinct PYRase Activity in Pseudomonas aeruginosa. Bioconjug Chem 2024; 35:472-479. [PMID: 38518220 PMCID: PMC11036351 DOI: 10.1021/acs.bioconjchem.4c00015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 02/26/2024] [Accepted: 03/18/2024] [Indexed: 03/24/2024]
Abstract
Pyrrolidone carboxyl peptidase, commonly known as PYRase, is an exopeptidase that catalytically cleaves an N-terminal pyroglutamic acid from peptides or proteins. The diverse functions of PYRases in bacterial enzymology have prompted the development of various bacterial diagnostic techniques. However, the specific physiological role and activity of this enzyme across the bacterial kingdom remain unclear. Here, we present a functional phenoxy-1,2-dioxetane chemiluminescent probe (PyrCL) that can selectively detect PYRase activity in both Gram-positive and Gram-negative bacteria. The probe activation mechanism is based on the cleavage of a pyroglutamyl substrate, followed by a release of the phenoxy-dioxetane luminophore, which then undergoes efficient chemiexcitation to emit a green photon. Probe PyrCL exhibits an effective turn-on response with superior detection capability in terms of response time and sensitivity compared to existing fluorescence probes. The superior detection sensitivity of the chemiluminescent probe enables us to reveal previously undetected PYRase activity in Streptococcus mutans. Furthermore, it enables the discrimination of Pseudomonas aeruginosa from other Gram-negative bacteria in the tested panel, based on their distinct PYRase activity. We expect that probe PyrCL will have great value for PYRase-based bacteria diagnosis with use in basic research and clinical applications.
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Affiliation(s)
- Rozan Tannous
- School
of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Omri Shelef
- School
of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Tal Kopp
- School
of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Micha Fridman
- School
of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Doron Shabat
- School
of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel Aviv 69978, Israel
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2
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Jiang H, Gong Q, Zhang R. Pyroglutamyl aminopeptidase 1 is a potential molecular target toward diagnosing and treating inflammation. Front Immunol 2023; 14:1301539. [PMID: 38098480 PMCID: PMC10720611 DOI: 10.3389/fimmu.2023.1301539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/17/2023] [Indexed: 12/17/2023] Open
Affiliation(s)
- Hongfei Jiang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
| | - Qiuyu Gong
- Department of Thoracic Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Renshuai Zhang
- The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China
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3
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Dhanalakshmi K, Kuramitsu S, Yokoyama S, Kumarevel T, Ponnuraj K. Crystal structure analysis of pyrrolidone carboxyl peptidase from Thermus thermophilus. Biophys Chem 2023; 293:106946. [PMID: 36563626 DOI: 10.1016/j.bpc.2022.106946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/06/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022]
Abstract
Pyrrolidone carboxyl peptidase (PCP) hydrolytically removes the L-pyroglutamic acid from the amino terminal region of pyroglutamyl proteins or peptides. So far, only a limited number of structures of PCP have been solved. Here we report the crystal structure of pyrrolidone carboxyl peptidase from Thermus thermophilus (TtPCP) which has been solved using the molecular replacement method and refined at 1.9 Å resolution. TtPCP follows the α/β/α architecture in which the central β-sheets are surrounded by α-helices on both sides. The inter subunit contact between two monomers consists of two short antiparallel β-strands and part of a long protrusion loop. By comparing the TtPCP with its structural homologs, we identified the putative catalytic triad residues as Glu76, Cys139 and His160. A unique disulfide link found in some homologs of TtPCP, formed between two monomers that provide thermal stability to the protein, is not observed in TtPCP. Hence, being a thermophilic protein, the putative thermal stability of TtPCP could be due to more intra and inter-molecular hydrogen bonds, hydrophobic and ion pair interactions when compared with its mesophilic counterpart. The structural details of TtPCP will be helpful to understand the basis of the intrinsic stability of thermophilic proteins. Also, it could be useful for protein engineering.
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Affiliation(s)
- K Dhanalakshmi
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India
| | - Seiki Kuramitsu
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Shigeyuki Yokoyama
- Structural Biology Laboratory, RIKEN Yokohama Institute, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
| | - Thirumananseri Kumarevel
- Structural Biology Laboratory, RIKEN Yokohama Institute, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan; Laboratory for Transcription Structural Biology, RIKEN Center for Biosystems Dynamic Research, RIKEN Yokohama Institute, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan.
| | - Karthe Ponnuraj
- Centre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India.
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Gormley M, Oliverio O, Kapidzic M, Ona K, Hall S, Fisher SJ. RNA profiling of laser microdissected human trophoblast subtypes at mid-gestation reveals a role for cannabinoid signaling in invasion. Development 2021; 148:272518. [PMID: 34557907 PMCID: PMC8572005 DOI: 10.1242/dev.199626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 08/26/2021] [Indexed: 12/13/2022]
Abstract
Human placental architecture is complex. Its surface epithelium, specialized for transport, forms by fusion of cytotrophoblast progenitors into multinucleated syncytiotrophoblasts. Near the uterine surface, these progenitors assume a different fate, becoming cancer-like cells that invade its lining and blood vessels. The latter process physically connects the placenta to the mother and shunts uterine blood to the syncytiotrophoblasts. Isolation of trophoblast subtypes is technically challenging. Upon removal, syncytiotrophoblasts disintegrate and invasive cytotrophoblasts are admixed with uterine cells. We used laser capture to circumvent these obstacles. This enabled isolation of syncytiotrophoblasts and two subpopulations of invasive cytotrophoblasts from cell columns and the endovascular compartment of spiral arteries. Transcriptional profiling revealed numerous genes, the placental or trophoblast expression of which was not known, including neurotensin and C4ORF36. Using mass spectrometry, discovery of differentially expressed mRNAs was extended to the protein level. We also found that invasive cytotrophoblasts expressed cannabinoid receptor 1. Unexpectedly, screening agonists and antagonists showed that signals from this receptor promote invasion. Together, these results revealed previously unseen gene expression patterns that translate to the protein level. Our data also suggested that endogenous and exogenous cannabinoids can affect human placental development. Summary: Transcriptomic and proteomic profiling of laser captured human trophoblasts showed that placental cells lining uterine arteries express cannabinoid receptor 1. Functional analyses suggest that endogenous/exogenous cannabinoids could affect placentation.
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Affiliation(s)
- Matthew Gormley
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA 94143, USA
| | - Oliver Oliverio
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA 94143, USA
| | - Mirhan Kapidzic
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA 94143, USA
| | - Katherine Ona
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA 94143, USA
| | - Steven Hall
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA 94143, USA
| | - Susan J Fisher
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Sciences, University of California, San Francisco, CA 94143, USA.,Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA 94143, USA.,Department of Anatomy, University of California, San Francisco, CA 94143, USA
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A Unique Carboxylic-Acid Hydrogen-Bond Network (CAHBN) Confers Glutaminyl Cyclase Activity on M28 Family Enzymes. J Mol Biol 2021; 433:166960. [PMID: 33774034 DOI: 10.1016/j.jmb.2021.166960] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/21/2021] [Accepted: 03/15/2021] [Indexed: 11/21/2022]
Abstract
Proteins with sequence or structure similar to those of di-Zn exopeptidases are usually classified as the M28-family enzymes, including the mammalian-type glutaminyl cyclases (QCs). QC catalyzes protein N-terminal pyroglutamate formation, a posttranslational modification important under many physiological and pathological conditions, and is a drug target for treating neurodegenerative diseases, cancers and inflammatory disorders. Without functional characterization, mammalian QCs and their orthologs remain indistinguishable at the sequence and structure levels from other M28-family proteins, leading to few reported QCs. Here, we show that a low-barrier carboxylic-acid hydrogen-bond network (CAHBN) is required for QC activity and discriminates QCs from M28-family peptidases. We demonstrate that the CAHBN-containing M28 peptidases deposited in the PDB are indeed QCs. Our analyses identify several thousands of QCs from the three domains of life, and we enzymatically and structurally characterize several. For the first time, the interplay between a CAHBN and the binuclear metal-binding center of mammalian QCs is made clear. We found that the presence or absence of CAHBN is a key discriminator for the formation of either the mono-Zn QCs or the di-Zn exopeptidases. Our study helps explain the possible roles of QCs in life.
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Ramirez-Expósito MJ, Martínez-Martos JM, Cantón-Habas V, Carrera-González MDP. Moderate Beer Consumption Modifies Tumoral Growth Parameters and Pyrrolidone Carboxypeptidase Type-I and Type-II Specific Activities in the Hypothalamus-Pituitary-Mammary Gland Axis in an Animal Model of Breast Cancer. Nutr Cancer 2020; 73:2695-2707. [PMID: 33305601 DOI: 10.1080/01635581.2020.1856891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
AIMS To determine the effect of moderate alcoholic and nonalcoholic beer consumption on tumoral growth parameters, the histopathology, pyrrolidone carboxypeptidase type I (Pcp I), and type II (Pcp II) specific activities in the hypothalamus-pituitary-mammary gland axis, and the circulating levels of estradiol (E2) and progesterone (P4) in rats with N-methyl-N-nitrosourea (NMU) induced mammary tumors. MATERIAL AND METHODS Food and drink intake, weight gain and tumor growth parameters were collected. The malignant phenotype of the tumor was performed using the Scarff-Bloom-Richardson grading method. Pcp specific activities were fluorometrically analyzed using pyroglutamyl-β-naphthylamide as substrate. Circulating steroid hormones were determined. RESULTS Differences were found in tumoral parameters, depending on the drink. Animals that were given alcohol-containing beer (A/C) beer to drink showed the lowest values of hypothalamic Pcp I, in association with the lowest levels of circulating E2. The significant decrease in Pcp I activity in all NMU-treated groups suggest a clear role of the Pcp I in the tumoral process, and A/C beer interferes with it. DISCUSSION Moderate consumption of alcoholic beer would have beneficial effects against mammary tumors through the modification of the endocrine status mediated by GnRH due to changes on Pcp I and II activities at different levels.
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Affiliation(s)
- María Jesús Ramirez-Expósito
- Department of Health Sciences, Faculty of Experimental and Health Sciences, University of Jaén, Jaén, Spain.,Experimental and Clinical Physiopathology Research Group CTS-1039, University of Jaén, Jaén, Spain
| | - José Manuel Martínez-Martos
- Department of Health Sciences, Faculty of Experimental and Health Sciences, University of Jaén, Jaén, Spain.,Experimental and Clinical Physiopathology Research Group CTS-1039, University of Jaén, Jaén, Spain
| | - Vanesa Cantón-Habas
- Department of Nursing, Pharmacology and Physiotherapy, Faculty of Medicine and Nursing, University of Cordoba. IMIBIC, Córdoba, Spain
| | - María Del Pilar Carrera-González
- Experimental and Clinical Physiopathology Research Group CTS-1039, University of Jaén, Jaén, Spain.,Department of Nursing, Pharmacology and Physiotherapy, Faculty of Medicine and Nursing, University of Cordoba. IMIBIC, Córdoba, Spain
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7
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Neoadjuvant chemotherapy modifies serum pyrrolidone carboxypeptidase specific activity in women with breast cancer and influences circulating levels of GnRH and gonadotropins. Breast Cancer Res Treat 2020; 182:751-760. [PMID: 32506336 DOI: 10.1007/s10549-020-05723-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 06/02/2020] [Indexed: 12/22/2022]
Abstract
PURPOSE Functional studies have demonstrated that gonadotropin-releasing hormone (GnRH) regulates cell proliferation, apoptosis, and tissue remodeling. GnRH is metabolized by the proteolytic regulatory enzyme pyrrolidone carboxypeptidase (Pcp) (E.C. 3.4.19.3), which is an omega peptidase widely distributed in fluids and tissues. We previously reported a decrease in both rat and human Pcp activity in breast cancer, suggesting that GnRH may be an important local hormonal factor in the pathogenesis of breast cancer. Recently, we have described that postmenopausal women with breast cancer show lower levels of serum Pcp activity than control postmenopausal women. To determine the effect of neoadjuvant chemotherapy (NACT) on serum Pcp specific activity and circulating levels of GnRH, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and steroid hormones 17-ß-estradiol and progesterone in pre- and postmenopausal women diagnosed with infiltrating ductal carcinoma. METHODS Serum Pcp activity was measured fluorometrically using pyroglutamyl-ß-naphthylamide. Circulating GnRH levels were dosed using a commercial RIA kit. Circulating LH and FSH levels were measured by enzyme immunoassays. Levels of steroid hormones were measured in serum samples by dissociation-enhanced lanthanide fluorescence immunoassay. RESULTS AND CONCLUSION Our results show the effect of NACT on the hypothalamic-pituitary axis, with the consequent alteration of circulating gonadotropins in premenopausal women with breast cancer. However, the results obtained in postmenopausal women with breast cancer treated with NACT, that is, the significant decrease in the concentration of GnRH and FSH compared to control postmenopausal women, differ from those obtained for premenopausal women. The only difference between pre- and postmenopausal women is their hormonal profile at the beginning of the study, that is, the presence of menopause and the consequent alteration of the hypothalamic-pituitary-gonadal axis.
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8
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Agrawal R, Singh R, Kumar A, Kumar A, Makde RD. Crystal structures of pyrrolidone-carboxylate peptidase I from Deinococcus radiodurans reveal the mechanism of L-pyroglutamate recognition. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2019; 75:308-316. [DOI: 10.1107/s2059798319000676] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 01/14/2019] [Indexed: 11/10/2022]
Abstract
Pyrrolidone-carboxylate peptidase (PCP) catalyzes the removal of an unusual amino acid, L-pyroglutamate (pG), from the N-termini of peptides and proteins. It has implications in the functional regulation of different peptides in both prokaryotes and eukaryotes. However, the pG-recognition mechanism of the PCP enzyme remains largely unknown. Here, crystal structures of PCP I from Deinococcus radiodurans (PCPdr) are reported in pG-free and pG-bound forms at resolutions of 1.73 and 1.55 Å, respectively. Four protomers in PCPdr form a tetrameric structure. The residues responsible for recognizing the pG residue are mostly contributed by a flexible loop (loop A) that is present near the active site. These residues are conserved in all known PCPs I, including those from mammals. Phe9 and Phe12 of loop A form stacking interactions with the pyrrolidone ring of pG, while Asn18 forms a hydrogen bond to OE of pG. The main chain of a nonconserved residue, Leu71, forms two hydrogen bonds to NH and OE of pG. Thus, pG is recognized in the S1 substrate subsite of the enzyme by both van der Waals and polar interactions, which provide specificity for the pG residue of the peptide. In contrast to previously reported PCP I structures, the PCPdr tetramer is in a closed conformation with an inaccessible active site. The structures show that the active site can be accessed by the substrates via disordering of loop A. This disordering could also prevent product inhibition by releasing the bound pG product from the S1 subsite, thus allowing the enzyme to engage a fresh substrate.
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9
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Kobayashi K, Abe Y, Harada H, Oota E, Endo T, Takeda H. Non-clinical pharmacokinetic profiles of rovatirelin, an orally available thyrotropin-releasing hormone analogue. Xenobiotica 2018; 49:106-119. [DOI: 10.1080/00498254.2017.1423130] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Kaoru Kobayashi
- Central Research Laboratories, Kissei Pharmaceutical Co., Ltd, Azumino, Nagano, Japan and
| | - Yoshikazu Abe
- Central Research Laboratories, Kissei Pharmaceutical Co., Ltd, Azumino, Nagano, Japan and
| | - Hiroshi Harada
- Central Research Laboratories, Kissei Pharmaceutical Co., Ltd, Azumino, Nagano, Japan and
| | - Emiko Oota
- Toxicological Laboratories, Kissei Pharmaceutical Co., Ltd, Azumino, Nagano, Japan
| | - Takuro Endo
- Central Research Laboratories, Kissei Pharmaceutical Co., Ltd, Azumino, Nagano, Japan and
| | - Hiroo Takeda
- Central Research Laboratories, Kissei Pharmaceutical Co., Ltd, Azumino, Nagano, Japan and
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The Coordination Abilities of Three Novel Analogues of Saliva Peptides: The Influence of Structural Modification on the Copper Binding. Int J Pept Res Ther 2017; 23:409-418. [PMID: 29170620 PMCID: PMC5681609 DOI: 10.1007/s10989-016-9569-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/16/2016] [Indexed: 11/16/2022]
Abstract
Three novel analogues of salivary peptides as sialorphin (QHNPR) and opiorphin (QRFSR) were synthesized by the solid-phase method. The sequences of these ligands were following: AHNPR, QANPR and QRFPR. The aim of our work was investigation in what way some structural modifications may impact on coordination abilities of studied peptides. In this work we presented the interaction of pentapeptides with copper(II) ions in wide range of pH. To determine the coordination model of ligands there were carried out several studies by spectroscopy (UV–Vis, CD) methods and potentiometric measurements.
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Edson JA, Kwon YJ. Design, challenge, and promise of stimuli-responsive nanoantibiotics. NANO CONVERGENCE 2016; 3:26. [PMID: 28191436 PMCID: PMC5271158 DOI: 10.1186/s40580-016-0085-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 09/22/2016] [Indexed: 05/18/2023]
Abstract
Over the past few years, there have been calls for novel antimicrobials to combat the rise of drug-resistant bacteria. While some promising new discoveries have met this call, it is not nearly enough. The major problem is that although these new promising antimicrobials serve as a short-term solution, they lack the potential to provide a long-term solution. The conventional method of creating new antibiotics relies heavily on the discovery of an antimicrobial compound from another microbe. This paradigm of development is flawed due to the fact that microbes can easily transfer a resistant mechanism if faced with an environmental pressure. Furthermore, there has been some evidence to indicate that the environment of the microbe can provide a hint as to their virulence. Because of this, the use of materials with antimicrobial properties has been garnering interest. Nanoantibiotics, (nAbts), provide a new way to circumvent the current paradigm of antimicrobial discovery and presents a novel mechanism of attack not found in microbes yet; which may lead to a longer-term solution against drug-resistance formation. This allows for environment-specific activation and efficacy of the nAbts but may also open up and create new design methods for various applications. These nAbts provide promise, but there is still ample work to be done in their development. This review looks at possible ways of improving and optimizing nAbts by making them stimuli-responsive, then consider the challenges ahead, and industrial applications.Graphical abstractA graphic detailing how the current paradigm of antibiotic discovery can be circumvented by the use of nanoantibiotics.
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Affiliation(s)
- Julius A. Edson
- Department of Chemical Engineering and Material Science, University of California, Irvine, Irvine, CA USA
| | - Young Jik Kwon
- Department of Chemical Engineering and Material Science, University of California, Irvine, Irvine, CA USA
- Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, CA USA
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA USA
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA USA
- 132 Sprague Hall, Irvine, CA USA
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12
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Next Generation Sequencing Identifies Five Major Classes of Potentially Therapeutic Enzymes Secreted by Lucilia sericata Medical Maggots. BIOMED RESEARCH INTERNATIONAL 2016; 2016:8285428. [PMID: 27119084 PMCID: PMC4826915 DOI: 10.1155/2016/8285428] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 03/07/2016] [Indexed: 01/01/2023]
Abstract
Lucilia sericata larvae are used as an alternative treatment for recalcitrant and chronic wounds. Their excretions/secretions contain molecules that facilitate tissue debridement, disinfect, or accelerate wound healing and have therefore been recognized as a potential source of novel therapeutic compounds. Among the substances present in excretions/secretions various peptidase activities promoting the wound healing processes have been detected but the peptidases responsible for these activities remain mostly unidentified. To explore these enzymes we applied next generation sequencing to analyze the transcriptomes of different maggot tissues (salivary glands, gut, and crop) associated with the production of excretions/secretions and/or with digestion as well as the rest of the larval body. As a result we obtained more than 123.8 million paired-end reads, which were assembled de novo using Trinity and Oases assemblers, yielding 41,421 contigs with an N50 contig length of 2.22 kb and a total length of 67.79 Mb. BLASTp analysis against the MEROPS database identified 1729 contigs in 577 clusters encoding five peptidase classes (serine, cysteine, aspartic, threonine, and metallopeptidases), which were assigned to 26 clans, 48 families, and 185 peptidase species. The individual enzymes were differentially expressed among maggot tissues and included peptidase activities related to the therapeutic effects of maggot excretions/secretions.
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13
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Dammers C, Gremer L, Reiß K, Klein AN, Neudecker P, Hartmann R, Sun N, Demuth HU, Schwarten M, Willbold D. Structural Analysis and Aggregation Propensity of Pyroglutamate Aβ(3-40) in Aqueous Trifluoroethanol. PLoS One 2015; 10:e0143647. [PMID: 26600248 PMCID: PMC4658145 DOI: 10.1371/journal.pone.0143647] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/06/2015] [Indexed: 12/23/2022] Open
Abstract
A hallmark of Alzheimer's disease (AD) is the accumulation of extracellular amyloid-β (Aβ) plaques in the brains of patients. N-terminally truncated pyroglutamate-modified Aβ (pEAβ) has been described as a major compound of Aβ species in senile plaques. pEAβ is more resistant to degradation, shows higher toxicity and has increased aggregation propensity and β-sheet stabilization compared to non-modified Aβ. Here we characterized recombinant pEAβ(3-40) in aqueous trifluoroethanol (TFE) solution regarding its aggregation propensity and structural changes in comparison to its non-pyroglutamate-modified variant Aβ(1-40). Secondary structure analysis by circular dichroism spectroscopy suggests that pEAβ(3-40) shows an increased tendency to form β-sheet-rich structures in 20% TFE containing solutions where Aβ(1-40) forms α-helices. Aggregation kinetics of pEAβ(3-40) in the presence of 20% TFE monitored by thioflavin-T (ThT) assay showed a typical sigmoidal aggregation in contrast to Aβ(1-40), which lacks ThT positive structures under the same conditions. Transmission electron microscopy confirms that pEAβ(3-40) aggregated to large fibrils and high molecular weight aggregates in spite of the presence of the helix stabilizing co-solvent TFE. High resolution NMR spectroscopy of recombinantly produced and uniformly isotope labeled [U-15N]-pEAβ(3-40) in TFE containing solutions indicates that the pyroglutamate formation affects significantly the N-terminal region, which in turn leads to decreased monomer stability and increased aggregation propensity.
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Affiliation(s)
- Christina Dammers
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Lothar Gremer
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225, Düsseldorf, Germany
| | - Kerstin Reiß
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Antonia N. Klein
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Philipp Neudecker
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225, Düsseldorf, Germany
| | - Rudolf Hartmann
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Na Sun
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Hans-Ulrich Demuth
- Fraunhofer Institute for Cell Therapy and Immunology, Department of Drug Design and Target Validation, 06120, Halle (Saale), Germany
| | - Melanie Schwarten
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Dieter Willbold
- Institute of Complex Systems (ICS-6) Structural Biochemistry, Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225, Düsseldorf, Germany
- * E-mail:
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Moradi SV, Varamini P, Toth I. Evaluation of the Biological Properties and the Enzymatic Stability of Glycosylated Luteinizing Hormone-Releasing Hormone Analogs. AAPS JOURNAL 2015; 17:1135-43. [PMID: 25956382 DOI: 10.1208/s12248-015-9769-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 04/06/2015] [Indexed: 12/15/2022]
Abstract
The enzymatic stability, antitumor activity, and gonadotropin stimulatory effects of glycosylated luteinizing hormone-releasing hormone (LHRH) analogs were investigated in this study. Conjugation of carbohydrate units, including lactose (Lac), glucose (GS), and galactose (Gal) to LHRH peptide protected the peptide from proteolytic degradation and increased the peptides' half-lives in human plasma, rat kidney membrane enzymes, and liver homogenate markedly. Among all seven modified analogs, compound 1 (Lac-[Q(1)][w(6)]LHRH) and compound 6 (GS(4)-[w(6)]LHRH) were stable in human plasma during 4 h of experiment. The half-lives of compounds 1 and 6 improved significantly in kidney membrane enzymes (from 3 min for LHRH to 68 and 103 min, respectively). The major cleavage sites for most of the glycosylated compounds were found to be at Trp(3)-Ser(4) and Ser(4)-Tyr(5) in compounds 1-5. Compound 6 was hydrolyzed at Ser(4)-Tyr(5) and the sugar conjugation site. The antiproliferative activity of the glycopeptides was evaluated on LHRH receptor-positive prostate cancer cells. The glycosylated LHRH derivatives had a significant growth inhibitory effect on the LNCaP cells after a 48-h treatment. It was demonstrated that compound 1 significantly increased the release of luteinizing hormone (LH) at 5 and 10 nM concentrations and compound 5 (GS-[Q(1)]LHRH) stimulated the release of follicle-stimulating hormone (FSH) at 5 nM concentration in dispersed rat pituitary cells (p < 0.05). In our studies, compound 1-bearing lactose and D-Trp was the most stable and active and is a promising candidate for future preclinical investigations in terms of in vitro biological activity and metabolic stability.
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Affiliation(s)
- Shayli Varasteh Moradi
- School of Chemistry and Molecular Biosciences, The University of Queensland, St. Lucia, Queensland, 4072, Australia
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15
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Brunetti L, Chiavaroli A, Cocco A, Ferrante C, Ferrucci A, Luisi G, Orlando G, Pinnen F, Vacca M. Synthesis and neuromodulatory effects of TRH-related peptides: inhibitory activity on catecholamine release in vitro. Pharmacol Rep 2013; 65:823-35. [PMID: 24145076 DOI: 10.1016/s1734-1140(13)71063-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 02/16/2013] [Indexed: 11/27/2022]
Abstract
BACKGROUND A detailed comprehension of central mechanisms underlying feeding behavior holds considerable promise for the treatment of alimentary disorders. METHODS In order to elucidate the tight interrelationships occurring at the hypothalamic neuronal endings between aminergic neurotransmitters and co-localized appetite modulators, we initially studied the effects of two anorexigenic peptides structurally related to thyrotropin-releasing hormone (TRH, 1), namely cyclo(His-Pro) (CHP, 2) and pGlu-His-Gly-OH (3), on [(3)H]-norepinephrine and [(3)H]-dopamine release from perfused rat hypothalamic synaptosomes. Furthermore, a number of TRH and CHP analogues were synthesized and tested for their ability to influence neurotransmitter release in the selected neuronal model. RESULTS Peptide 3 showed only a slight inhibitory activity on norepinephrine release, whereas no effect was observed for compound 2. TRH analogue 8, metabolically stabilized by the replacement of pyroglutamate with the pyrohomocysteic acid (pHcs), was found to be inactive. Conversely, a significant inhibitory effect on dopamine and norepinephrine release was observed for the CHP-related diketopiperazines cyclo(Leu-Pro) (11) and cyclo(His-Gly) (14). CONCLUSIONS These results suggest a potential role for cyclo-dipeptides 11 and 14 in the hypothalamic modulation of appetite suppressant circuitry.
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Affiliation(s)
- Luigi Brunetti
- Department of Pharmacy, G. d'Annunzio University, via dei Vestini 31, 66013 Chieti, Italy.
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16
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Kamysz E, Sałaga M, Sobczak M, Kamysz W, Fichna J. Characterization of the effects of opiorphin and sialorphin and their analogs substituted in position 1 with pyroglutamic acid on motility in the mouse ileum. J Pept Sci 2013; 19:166-72. [PMID: 23381913 DOI: 10.1002/psc.2486] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Revised: 12/30/2012] [Accepted: 01/08/2013] [Indexed: 12/21/2022]
Abstract
Opiorphin and sialorphin are two recently discovered endogenous enkephalin-degrading enzyme inhibitors. Our aim was to characterize their effect on the mouse ileum motility and to investigate the role of glutamine in position 1. Opiorphin, sialorphin, and their analogs substituted in position 1 with pyroglutamic acid (pGlu) were synthesized by the solid-phase method using Fmoc chemistry. The effect of peptides on gastrointestinal (GI) motility was characterized using in vitro assays and in mouse model of upper GI transit. Opiorphin and sialorphin, but not their analogs, significantly increased electrical field-stimulated contractions in the mouse ileum in a δ-opioid receptor-dependent manner. Opiorphin, sialorphin, and their analogs did not influence the effect of [Met(5)]enkephalin on smooth muscle contractility in the mouse ileum in vitro. [Met(5)]enkephalin and sialorphin, but not opiorphin injected intravenously (1 mg/kg), significantly inhibited the upper GI transit. The intraperitoneal administration of peptides (3 mg/kg) did not change the mouse upper GI transit. In conclusion, this is the first study investigating the effect of opiorphin and sialorphin on the mouse ileum motility and demonstrating that glutamine in position 1 is crucial for their pharmacological action. Our results may be important for further structure-activity relationship studies on opiorphin and sialorphin and future development of potent clinical therapeutics aiming at the enkephalinergic system.
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Affiliation(s)
- Elżbieta Kamysz
- Department of Organic Chemistry, Faculty of Chemistry, University of Gdansk, Gdansk, Poland
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17
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Ho HY, Cheng ML, Shiao MS, Chiu DTY. Characterization of global metabolic responses of glucose-6-phosphate dehydrogenase-deficient hepatoma cells to diamide-induced oxidative stress. Free Radic Biol Med 2013; 54:71-84. [PMID: 23142419 DOI: 10.1016/j.freeradbiomed.2012.10.557] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 10/06/2012] [Accepted: 10/29/2012] [Indexed: 12/30/2022]
Abstract
Glucose-6-phosphate dehydrogenase (G6PD) is crucial to NADPH generation and redox homeostasis. We have recently shown that G6PD deficiency predisposes cells to oxidant-induced cell death, and it is associated with the impairment of glutathione regeneration. It remains unclear what other metabolic pathways are affected by G6PD deficiency and whether the altered metabolism disturbs cellular redox homeostasis and underlies increased susceptibility to oxidants. In this study, we examined the effects of diamide on global metabolite profiles of SK-Hep1-derived SK-i-Gi and SK-i-Sc cells, which could inducibly express short hairpin RNA (shRNA) against G6PD (Gi) and control shRNA (Sc), respectively. There was no significant difference in their metabolite profiles under uninduced conditions. Doxycycline (Dox) addition resulted in over 70% decrease in G6PD activity in SK-i-Gi cells. This was accompanied by relatively minor changes in the metabolome of SK-i-Gi cells. Upon further diamide treatment, the metabolite profiles of both SK-i-Gi and SK-i-Sc cells changed in a time-dependent manner. A number of metabolic pathways, including those involved in energy metabolism and metabolism of amino acids and glutathione, were affected. However, the changes in the metabolite profile of Dox-treated SK-i-Gi cells were distinct from those of control cells (i.e., Dox-treated SK-i-Sc, SK-i-Gi, and SK-i-Sc cells). Cellular glutathione was depleted, whereas its disulfide form increased significantly in diamide, Dox-treated SK-i-Gi cells. Metabolites related to energy metabolism, such as AMP, ADP, and acetylcarnitine, increased to a greater extent in these cells than in diamide-treated control cells. In contrast, NAD and glutathione dropped to lower levels in SK-i-Gi cells than in control cells. The NAD(+) depletion in SK-i-Gi cells was accompanied by a significant increase in NAD kinase activity. Targeted analyses revealed that NADP(+) and NADPH increased significantly in diamide, Dox-treated SK-i-Gi cells compared with similarly treated control cells. Our results suggest that diamide induces oxidation and depletion of glutathione in SK-i-Gi cells under conditions of G6PD shRNA induction and subsequently induces conversion of NAD(+) to NADP(+) through enhanced NAD kinase activity. This may represent a compensatory mechanism to restore cellular NADPH reserve in G6PD-deficient cells. It is accompanied by alteration in pathways of cellular energy metabolism, such as glycolysis and β-oxidation.
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Affiliation(s)
- Hung-Yao Ho
- Department of Medical Biotechnology and Laboratory Science, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan.
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18
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Gramer MJ. Product Quality Considerations for Mammalian Cell Culture Process Development and Manufacturing. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2013; 139:123-66. [DOI: 10.1007/10_2013_214] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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19
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Carrera-González MDP, Ramírez-Expósito MJ, Dueñas B, Martínez-Ferrol J, Mayas MD, Martínez-Martos JM. Putative relationship between hormonal status and serum pyrrolidone carboxypeptidase activity in pre- and post- menopausal women with breast cancer. Breast 2012; 21:751-4. [DOI: 10.1016/j.breast.2012.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 01/10/2012] [Accepted: 02/05/2012] [Indexed: 10/28/2022] Open
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20
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Sun N, Hartmann R, Lecher J, Stoldt M, Funke SA, Gremer L, Ludwig HH, Demuth HU, Kleinschmidt M, Willbold D. Structural analysis of the pyroglutamate-modified isoform of the Alzheimer's disease-related amyloid-β using NMR spectroscopy. J Pept Sci 2012; 18:691-5. [DOI: 10.1002/psc.2456] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 08/01/2012] [Accepted: 08/31/2012] [Indexed: 11/08/2022]
Affiliation(s)
- Na Sun
- ICS-6, Forschungszentrum Jülich; 52425 Jülich Germany
| | | | - Justin Lecher
- ICS-6, Forschungszentrum Jülich; 52425 Jülich Germany
| | - Matthias Stoldt
- ICS-6, Forschungszentrum Jülich; 52425 Jülich Germany
- Institut für Physikalische Biologie; Heinrich-Heine-Universität; 40225 Düsseldorf Germany
| | | | - Lothar Gremer
- ICS-6, Forschungszentrum Jülich; 52425 Jülich Germany
| | | | | | | | - Dieter Willbold
- ICS-6, Forschungszentrum Jülich; 52425 Jülich Germany
- Institut für Physikalische Biologie; Heinrich-Heine-Universität; 40225 Düsseldorf Germany
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21
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22
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Zheng LL, Niu S, Hao P, Feng K, Cai YD, Li Y. Prediction of protein modification sites of pyrrolidone carboxylic acid using mRMR feature selection and analysis. PLoS One 2011; 6:e28221. [PMID: 22174779 PMCID: PMC3235115 DOI: 10.1371/journal.pone.0028221] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Accepted: 11/03/2011] [Indexed: 11/18/2022] Open
Abstract
Pyrrolidone carboxylic acid (PCA) is formed during a common post-translational modification (PTM) of extracellular and multi-pass membrane proteins. In this study, we developed a new predictor to predict the modification sites of PCA based on maximum relevance minimum redundancy (mRMR) and incremental feature selection (IFS). We incorporated 727 features that belonged to 7 kinds of protein properties to predict the modification sites, including sequence conservation, residual disorder, amino acid factor, secondary structure and solvent accessibility, gain/loss of amino acid during evolution, propensity of amino acid to be conserved at protein-protein interface and protein surface, and deviation of side chain carbon atom number. Among these 727 features, 244 features were selected by mRMR and IFS as the optimized features for the prediction, with which the prediction model achieved a maximum of MCC of 0.7812. Feature analysis showed that all feature types contributed to the modification process. Further site-specific feature analysis showed that the features derived from PCA's surrounding sites contributed more to the determination of PCA sites than other sites. The detailed feature analysis in this paper might provide important clues for understanding the mechanism of the PCA formation and guide relevant experimental validations.
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Affiliation(s)
- Lu-Lu Zheng
- Hubei Bioinformatics and Molecular Imaging Key Laboratory, Huazhong University of Science and Technology, Wuhan, China
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23
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Lo YC, Su WC, Ko TP, Wang NC, Wang AHJ. Terpyridine Platinum(II) Complexes Inhibit Cysteine Proteases by Binding to Active-site Cysteine. J Biomol Struct Dyn 2011; 29:267-82. [DOI: 10.1080/073911011010524993] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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24
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Drew SC, Masters CL, Barnham KJ. Alzheimer's Aβ peptides with disease-associated N-terminal modifications: influence of isomerisation, truncation and mutation on Cu2+ coordination. PLoS One 2010; 5:e15875. [PMID: 21209855 PMCID: PMC3012727 DOI: 10.1371/journal.pone.0015875] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Accepted: 11/29/2010] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The amyloid-β (Aβ) peptide is the primary component of the extracellular senile plaques characteristic of Alzheimer's disease (AD). The metals hypothesis implicates redox-active copper ions in the pathogenesis of AD and the Cu(2+) coordination of various Aβ peptides has been widely studied. A number of disease-associated modifications involving the first 3 residues are known, including isomerisation, mutation, truncation and cyclisation, but are yet to be characterised in detail. In particular, Aβ in plaques contain a significant amount of truncated pyroglutamate species, which appear to correlate with disease progression. METHODOLOGY/PRINCIPAL FINDINGS We previously characterised three Cu(2+)/Aβ1-16 coordination modes in the physiological pH range that involve the first two residues. Based upon our finding that the carbonyl of Ala2 is a Cu(2+) ligand, here we speculate on a hypothetical Cu(2+)-mediated intramolecular cleavage mechanism as a source of truncations beginning at residue 3. Using EPR spectroscopy and site-specific isotopic labelling, we have also examined four Aβ peptides with biologically relevant N-terminal modifications, Aβ1[isoAsp]-16, Aβ1-16(A2V), Aβ3-16 and Aβ3[pE]-16. The recessive A2V mutation preserved the first coordination sphere of Cu(2+)/Aβ, but altered the outer coordination sphere. Isomerisation of Asp1 produced a single dominant species involving a stable 5-membered Cu(2+) chelate at the amino terminus. The Aβ3-16 and Aβ3[pE]-16 peptides both exhibited an equilibrium between two Cu(2+) coordination modes between pH 6-9 with nominally the same first coordination sphere, but with a dramatically different pH dependence arising from differences in H-bonding interactions at the N-terminus. CONCLUSIONS/SIGNIFICANCE N-terminal modifications significantly influence the Cu(2+) coordination of Aβ, which may be critical for alterations in aggregation propensity, redox-activity, resistance to degradation and the generation of the Aβ3-× (× = 40/42) precursor of disease-associated Aβ3[pE]-x species.
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Affiliation(s)
- Simon C Drew
- Department of Pathology, The University of Melbourne, Melbourne, Victoria, Australia.
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25
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Ding F, Li HH, Li J, Myers RM, Francke U. Neonatal maternal deprivation response and developmental changes in gene expression revealed by hypothalamic gene expression profiling in mice. PLoS One 2010; 5:e9402. [PMID: 20195375 PMCID: PMC2827556 DOI: 10.1371/journal.pone.0009402] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Accepted: 01/14/2010] [Indexed: 02/07/2023] Open
Abstract
Neonatal feeding problems are observed in several genetic diseases including Prader-Willi syndrome (PWS). Later in life, individuals with PWS develop hyperphagia and obesity due to lack of appetite control. We hypothesized that failure to thrive in infancy and later-onset hyperphagia are related and could be due to a defect in the hypothalamus. In this study, we performed gene expression microarray analysis of the hypothalamic response to maternal deprivation in neonatal wild-type and Snord116del mice, a mouse model for PWS in which a cluster of imprinted C/D box snoRNAs is deleted. The neonatal starvation response in both strains was dramatically different from that reported in adult rodents. Genes that are affected by adult starvation showed no expression change in the hypothalamus of 5 day-old pups after 6 hours of maternal deprivation. Unlike in adult rodents, expression levels of Nanos2 and Pdk4 were increased, and those of Pgpep1, Ndp, Brms1l, Mett10d, and Snx1 were decreased after neonatal deprivation. In addition, we compared hypothalamic gene expression profiles at postnatal days 5 and 13 and observed significant developmental changes. Notably, the gene expression profiles of Snord116del deletion mice and wild-type littermates were very similar at all time points and conditions, arguing against a role of Snord116 in feeding regulation in the neonatal period.
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Affiliation(s)
- Feng Ding
- Department of Genetics, Stanford University, Stanford, California, United States of America
| | - Hong Hua Li
- Department of Genetics, Stanford University, Stanford, California, United States of America
| | - Jun Li
- Department of Genetics, Stanford University, Stanford, California, United States of America
| | - Richard M. Myers
- Department of Genetics, Stanford University, Stanford, California, United States of America
| | - Uta Francke
- Department of Genetics, Stanford University, Stanford, California, United States of America
- * E-mail:
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26
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Cuervo P, Domont GB, De Jesus JB. Proteomics of trypanosomatids of human medical importance. J Proteomics 2010; 73:845-67. [PMID: 20056176 DOI: 10.1016/j.jprot.2009.12.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2009] [Accepted: 12/18/2009] [Indexed: 12/31/2022]
Abstract
Leishmania spp., Trypanosoma cruzi, and Trypanosoma brucei are protozoan parasites that cause a spectrum of fatal human diseases around the world. Recent completion of the genomic sequencing of these parasites has enormous relevance to the study of their biology and the pathogenesis of the diseases they cause because it opens the door to high-throughput proteomic technologies. This review encompasses studies using diverse proteomic approaches with these organisms to describe and catalogue global protein profiles, reveal changes in protein expression during development, elucidate the subcellular localisation of gene products, and evaluate host-parasite interactions.
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Affiliation(s)
- Patricia Cuervo
- Laboratorio de Pesquisa em Leishmaniose, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
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27
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Marinho CE, Almeida-Santos SM, Carneiro SM, Yamasaki SC, Silveira PF. Peptidase activities in Crotalus durissus terrificus semen. Reproduction 2008; 136:767-76. [DOI: 10.1530/rep-08-0192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AbstractTo understand the role of peptidases in seminal physiology ofCrotalus durissus terrificus, activity levels of representative enzymes in semen and their sensitivities to inhibitors, cofactors, and peptide hormones were evaluated. The existence of seminal fractions and the association of peptidases with these fractions were also characterized for the first time in snakes. The prominent inhibitors of aminopeptidases (APs) were amastatin for acid, basic, and neutral; bestatin for basic; and diprotin A for dipeptidyl-IV. Cystyl and prolyl-imino APs were similarly susceptible to the majority of these inhibitors. The basic and neutral were characterized as metallo-peptidases, acid AP was activated by MnCl2, and cystyl, prolyl-imino, and type I pyroglutamyl were characterized as sulphydryl-dependent APs. Angiotensin II, vasotocin, bradykinin, fertilization-promoting peptide, and TRH altered the majority of these peptidase activities; these peptides are possible substrates and/or modulators of these peptidases. Peptidase activities were found in all seminal fractions: seminal plasma (SP), prostasome-like (PR) structures, and soluble (S-) and membrane-bound fractions (MFs) of spermatozoa. The levels of activity of each peptidase varied among different seminal fractions. In SP, the higher activities were puromycin-insensitive neutral and basic APs. In PR, the higher activity was puromycin-insensitive neutral AP. In spermatozoa, the higher activity in subcellular SF was puromycin-sensitive neutral, while in MF both puromycin-sensitive and -insensitive neutral APs were equally higher than the other examined peptidases. Data suggested that these peptidases, mainly basic and neutral, have a high relevance in regulating seminal functions ofC. d. terrificus.
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Chronic ethanol intake modifies pyrrolidon carboxypeptidase activity in mouse frontal cortex synaptosomes under resting and K+ -stimulated conditions: role of calcium. Neurosci Lett 2008; 439:75-8. [PMID: 18501515 DOI: 10.1016/j.neulet.2008.04.093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2007] [Revised: 04/23/2008] [Accepted: 04/29/2008] [Indexed: 11/22/2022]
Abstract
Pyrrolidon carboxypeptidase (Pcp) is an omega peptidase that removes pyroglutamyl N-terminal residues of peptides such as thyrotrophin-releasing hormone (TRH), which is one of the neuropeptides that has been localized into many areas of the brain and acts as an endogenous neuromodulator of several parameters related to ethanol (EtOH) consumption. In this study, we analysed the effects of chronic EtOH intake on Pcp activity on mouse frontal cortex synaptosomes and their corresponding supernatant under basal and K+ -stimulated conditions, in presence and absence of calcium (Ca2+) to know the regulation of Pcp on TRH. In basal conditions, chronic EtOH intake significantly decreased synaptosomes Pcp activity but only in absence of Ca2+. However, supernatant Pcp activity is also decreased in presence and absence of calcium. Under K+-stimulated conditions, chronic EtOH intake decreased synaptosomes Pcp activity but only in absence of Ca2+, whereas supernatant Pcp activity was significantly decreased only in presence of Ca2+. The general inhibitory effect of chronic EtOH intake on Pcp activity suggests an inhibition of TRH metabolism and an enhancement of TRH neurotransmitter/neuromodulator functions, which could be related to putative processes of tolerance to EtOH in which TRH has been involved. Our data may also indicate that active peptides and their degrading peptidases are released together to the synaptic cleft to regulate the neurotransmitter/neuromodulator functions of these peptides, through a Ca2+ -dependent mechanism.
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Zambotti-Villela L, Yamasaki SC, Villarroel JS, Alponti RF, Silveira PF. Prospective evaluation of aminopeptidase activities in plasma and peripheral organs of streptozotocin-induced diabetic rats. J Endocrinol Invest 2008; 31:492-8. [PMID: 18591879 DOI: 10.1007/bf03346396] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The cleavage of peptides by aminopeptidase enzyme types could be among the mechanisms related to certain disruptions on mediator and modulatory functions in diabetes mellitus. In order to examine this hypothesis, we measured representative aminopeptidase activities in tissues of peripheral organs of control and streptozotocin-diabetic rats. None of the examined aminopeptidase activities differed between diabetics and controls in plasma, ileum, stomach or lung. Soluble and membrane-associated alanyl, and membrane-associated cystyl aminopeptidase activities were higher in the kidney of diabetics. Decreased activity was observed in soluble and membrane-associated aspartyl and soluble dipeptidyl-peptidase IV, while increased activity was observed in soluble alanyl, arginyl, and cystyl aminopeptidases in the pancreas of diabetics. In the jejunum, soluble cystyl aminopeptidase increased in diabetics. Soluble arginyl and type-1-pyroglutamyl aminopeptidase and membrane-associated dipeptidyl-peptidase IV activities increased in the liver of diabetics. Membrane-associated dipeptidyl-peptidase IV and alanyl aminopeptidase activities in the spleen were higher in diabetics than in controls. Membrane-associated alanyl aminopeptidase activity also increased in the heart of diabetics. All these changes in streptozotocin-treated rats were avoided by the administration of insulin. Our comparative analysis of a diverse array of aminopeptidase activities supported the proposal that the regulation of peptide cleavage by these enzyme types is associated with the effects of streptozotocin-diabetes mellitus on peripheral organs.
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Affiliation(s)
- L Zambotti-Villela
- Laboratory of Pharmacology, Instituto Butantan, 05503-900 São Paulo, SP, Brazil
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De Jesus JB, Cuervo P, Junqueira M, Britto C, Silva-Filho FC, Sabóia-Vahia L, González LJ, Barbosa Domont G. Application of two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for proteomic analysis of the sexually transmitted parasite Trichomonas vaginalis. JOURNAL OF MASS SPECTROMETRY : JMS 2007; 42:1463-1473. [PMID: 17960578 DOI: 10.1002/jms.1286] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Trichomonas vaginalis is a sexually transmitted protozoan parasite that infects the human urogenital tract causing trichomoniasis, a worldwide disease. In this work, a fresh clinical isolate of T. vaginalis was used for study of the protein expression in this species. Two-dimensional gel electrophoresis (2-DE) and MALDI-TOF/TOF mass spectrometry (MS) were employed to create a reference map of soluble proteins in the pH range 4-7. A set of 116 proteins belonging to functional classes expressed in high and low abundance was identified by peptide mass fingerprinting and tandem MS. These identifications corresponded to 67 different proteins, suggesting that post-translational modifications are common phenomena in T. vaginalis. Identified proteins were classified into 16 groups according to biological processes. Among detected proteins we identified the major enzymes involved in both cytosolic and hydrogenosomal metabolic pathways, as well as putative protein targets for new drug design. In addition, this analysis allows validation of previous gene predictions confirming the expression of 15 hypothetical proteins. Finally, the findings here reported represent the first reference proteome map of T. vaginalis and the first steps towards the description of a comprehensive proteome map of this parasite.
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Affiliation(s)
- Jose Batista De Jesus
- Laboratório de Biologia Molecular e Doenças Endêmicas, Departamento de Bioquímica e Biologia Molecular, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil
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Zambotti-Villela L, Yamasaki SC, Villarroel JS, Murena-Nunes C, Silveira PF. Prolyl, cystyl and pyroglutamyl peptidase activities in the hippocampus and hypothalamus of streptozotocin-induced diabetic rats. Peptides 2007; 28:1586-95. [PMID: 17698248 DOI: 10.1016/j.peptides.2007.07.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 07/12/2007] [Accepted: 07/13/2007] [Indexed: 01/21/2023]
Abstract
Prolyl, cystyl and pyroglutamyl peptidases are emerging targets for diabetes and cognitive deficit therapies. The present study is focused on the influence of diabetes mellitus induced by streptozotocin on levels of representative hydrolytic activities of these enzymes in the rat hypothalamus and hippocampus. Streptozotocin-diabetic rats presented about 348mg glucose/dL blood, and a slightly increased hematocrit and plasma osmolality. The activities of soluble and membrane-bound dipeptidyl-peptidase IV, and soluble cystyl aminopeptidase did not differ between diabetic and control rats in both brain areas. Hippocampal soluble prolyl oligopeptidase presented similar activities between diabetic and controls. Increased activities in diabetics were observed for soluble prolyl oligopeptidase (1.78-fold) and membrane-bound cystyl aminopeptidase (2.55-fold) in the hypothalamus, and for membrane-bound cystyl aminopeptidase (5.14-fold) in the hippocampus. In both brain areas, the activities of membrane-bound and soluble pyroglutamyl aminopeptidase were slightly lower (<0.7-fold) in diabetics. All modifications (except hematocrit) observed in streptozotocin-treated rats were mitigated by the administration of insulin. Glucose and/or insulin were shown to alter in vitro the hypothalamic activities of soluble pyroglutamyl aminopeptidase and prolyl oligopeptidase, as well as membrane-bound cystyl aminopeptidase. These data provide the first evidence that diabetes mellitus generates direct and indirect effects on the activity levels of brain peptidases. The implied regional control of regulatory peptide activity by these peptidases suggests novel potential approaches to understand certain disruptions on mediator and modulatory functions in diabetes mellitus.
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Affiliation(s)
- Leonardo Zambotti-Villela
- Laboratory of Pharmacology, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900 São Paulo, SP, Brazil
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Cuervo P, de Jesus JB, Junqueira M, Mendonça-Lima L, González LJ, Betancourt L, Grimaldi G, Domont GB, Fernandes O, Cupolillo E. Proteome analysis of Leishmania (Viannia) braziliensis by two-dimensional gel electrophoresis and mass spectrometry. Mol Biochem Parasitol 2007; 154:6-21. [PMID: 17499861 DOI: 10.1016/j.molbiopara.2007.03.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 03/12/2007] [Accepted: 03/21/2007] [Indexed: 10/23/2022]
Abstract
Leishmania (Viannia) braziliensis, a protozoan parasite widespread in the New World, is responsible for the infection of different mammal orders, including humans. This species is considered to be a major etiological agent of American cutaneous leishmaniasis. A proteomic study was carried out to identify proteins expressed by L. (V.) braziliensis. One hundred and one spots representing 75 protein entries were identified by MALDI-TOF-TOF. Isoelectric point values estimated by gel electrophoresis matched closely with predicted values, although some discrepancies existed suggesting that post-translational protein modifications may be common in L. braziliensis. Moreover, 20 hypothetical proteins were experimentally identified. Identified proteins were classified into 15 groups according to biological process. Among the proteins identified, approximately 40% have not been previously reported in a proteomic map of Leishmania. In addition, a number of potential virulence factors and drug targets were identified in this protein map, including some proteins associated with the metastatic phenotype. This study describes the first compilation of a proteomic reference map for L. braziliensis (pI 4-7, M(r) 10-130 kDa) and provides a very useful tool for comparative studies of strains isolated from patients presenting different clinical manifestations of leishmaniasis as well as a potential tool to identify markers for clinical diagnosis, therapeutics, and prognosis.
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Affiliation(s)
- Patricia Cuervo
- Departamento de Imunologia, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Manguinhos, 21045-900 Rio de Janeiro, RJ, Brazil
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Rucktooa P, Antoine R, Herrou J, Huvent I, Locht C, Jacob-Dubuisson F, Villeret V, Bompard C. Crystal structures of two Bordetella pertussis periplasmic receptors contribute to defining a novel pyroglutamic acid binding DctP subfamily. J Mol Biol 2007; 370:93-106. [PMID: 17499270 DOI: 10.1016/j.jmb.2007.04.047] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 04/10/2007] [Accepted: 04/17/2007] [Indexed: 11/22/2022]
Abstract
Gram-negative bacteria have developed several different transport systems for solute uptake. One of these, the tripartite ATP independent periplasmic transport system (TRAP-T), makes use of an extracytoplasmic solute receptor (ESR) which captures specific solutes with high affinity and transfers them to their partner permease complex located in the bacterial inner membrane. We hereby report the structures of DctP6 and DctP7, two such ESRs from Bordetella pertussis. These two proteins display a high degree of sequence and structural similarity and possess the "Venus flytrap" fold characteristic of ESRs, comprising two globular alpha/beta domains hinged together to form a ligand binding cleft. DctP6 and DctP7 both show a closed conformation due to the presence of one pyroglutamic acid molecule bound by highly conserved residues in their respective ligand binding sites. BLAST analyses have revealed that the DctP6 and DctP7 residues involved in ligand binding are strictly present in a number of predicted TRAP-T ESRs from other bacteria. In most cases, the genes encoding these TRAP-T systems are located in the vicinity of a gene coding for a pyroglutamic acid metabolising enzyme. Both the high degree of conservation of these ligand binding residues and the genomic context of these TRAP-T-coding operons in a number of bacterial species, suggest that DctP6 and DctP7 constitute the prototypes of a novel TRAP-T DctP subfamily involved in pyroglutamic acid transport.
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Affiliation(s)
- Prakash Rucktooa
- UMR 8161 CNRS Institut de Biologie de Lille, Laboratoire de Cristallographie Macromoléculaire, Université des Sciences et Technologies de Lille, Université de Lille 2, Institut Pasteur de Lille IFR142, Lille cedex, France
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Xie H, Vucetic S, Iakoucheva LM, Oldfield CJ, Dunker AK, Obradovic Z, Uversky VN. Functional anthology of intrinsic disorder. 3. Ligands, post-translational modifications, and diseases associated with intrinsically disordered proteins. J Proteome Res 2007; 6:1917-32. [PMID: 17391016 PMCID: PMC2588348 DOI: 10.1021/pr060394e] [Citation(s) in RCA: 298] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Currently, the understanding of the relationships between function, amino acid sequence, and protein structure continues to represent one of the major challenges of the modern protein science. As many as 50% of eukaryotic proteins are likely to contain functionally important long disordered regions. Many proteins are wholly disordered but still possess numerous biologically important functions. However, the number of experimentally confirmed disordered proteins with known biological functions is substantially smaller than their actual number in nature. Therefore, there is a crucial need for novel bionformatics approaches that allow projection of the current knowledge from a few experimentally verified examples to much larger groups of known and potential proteins. The elaboration of a bioinformatics tool for the analysis of functional diversity of intrinsically disordered proteins and application of this data mining tool to >200 000 proteins from the Swiss-Prot database, each annotated with at least one of the 875 functional keywords, was described in the first paper of this series (Xie, H.; Vucetic, S.; Iakoucheva, L. M.; Oldfield, C. J.; Dunker, A. K.; Obradovic, Z.; Uversky, V.N. Functional anthology of intrinsic disorder. 1. Biological processes and functions of proteins with long disordered regions. J. Proteome Res. 2007, 5, 1882-1898). Using this tool, we have found that out of the 710 Swiss-Prot functional keywords associated with at least 20 proteins, 262 were strongly positively correlated with long intrinsically disordered regions, and 302 were strongly negatively correlated. Illustrative examples of functional disorder or order were found for the vast majority of keywords showing strongest positive or negative correlation with intrinsic disorder, respectively. Some 80 Swiss-Prot keywords associated with disorder- and order-driven biological processes and protein functions were described in the first paper (see above). The second paper of the series was devoted to the presentation of 87 Swiss-Prot keywords attributed to the cellular components, domains, technical terms, developmental processes, and coding sequence diversities possessing strong positive and negative correlation with long disordered regions (Vucetic, S.; Xie, H.; Iakoucheva, L. M.; Oldfield, C. J.; Dunker, A. K.; Obradovic, Z.; Uversky, V. N. Functional anthology of intrinsic disorder. 2. Cellular components, domains, technical terms, developmental processes, and coding sequence diversities correlated with long disordered regions. J. Proteome Res. 2007, 5, 1899-1916). Protein structure and functionality can be modulated by various post-translational modifications or/and as a result of binding of specific ligands. Numerous human diseases are associated with protein misfolding/misassembly/misfunctioning. This work concludes the series of papers dedicated to the functional anthology of intrinsic disorder and describes approximately 80 Swiss-Prot functional keywords that are related to ligands, post-translational modifications, and diseases possessing strong positive or negative correlation with the predicted long disordered regions in proteins.
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Affiliation(s)
- Hongbo Xie
- Center for Information Science and Technology, Temple University, Philadelphia, PA 19122
| | - Slobodan Vucetic
- Center for Information Science and Technology, Temple University, Philadelphia, PA 19122
| | - Lilia M. Iakoucheva
- Laboratory of Statistical Genetics, The Rockefeller University, New York, NY 10021
| | - Christopher J. Oldfield
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University, School of Medicine, Indianapolis, IN 46202
| | - A. Keith Dunker
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University, School of Medicine, Indianapolis, IN 46202
| | - Zoran Obradovic
- Center for Information Science and Technology, Temple University, Philadelphia, PA 19122
| | - Vladimir N. Uversky
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University, School of Medicine, Indianapolis, IN 46202
- Institute for Biological Instrumentation, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
- Correspondence should be addressed to: Vladimir N. Uversky, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, 635 Barnhill Drive, MS#4021, Indianapolis, IN 46202, USA; Phone: 317-278-9194; Fax: 317-274-4686; E-mail:
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Nguyen V, Zharikova AD, Prokai L. Evidence for interplay between thyrotropin-releasing hormone (TRH) and its structural analogue pGlu-Glu-Pro-NH2 ([Glu2]TRH) in the brain: an in vivo microdialysis study. Neurosci Lett 2006; 415:64-7. [PMID: 17234338 DOI: 10.1016/j.neulet.2006.12.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2006] [Revised: 12/19/2006] [Accepted: 12/26/2006] [Indexed: 11/18/2022]
Abstract
Local perfusion of pGlu-Glu-Pro-NH2, an endogenous peptide structurally related to thyrotropine-releasing hormone (TRH), via in vivo microdialysis into the rat hippocampus did not change the basal level of extracellular acetylcholine. However, co-perfusion of pGlu-Glu-Pro-NH2 with TRH in equimolar concentrations yielded a significant attenuation of TRH-induced acetylcholine release. The results have supported the study's hypothesis that pGlu-Glu-Pro-NH2 opposes the cholinergic effect of TRH in the mammalian central nervous system. The enantiomer pGlu-d-Glu-Pro-NH2 affected neither basal extracellular nor TRH-induced increase of acetylcholine levels.
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Affiliation(s)
- Vien Nguyen
- Department of Molecular Biology & Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107-2699, USA
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Kilbane Z, Vaas PR, Cuív PO, O'Connor B. Cloning and heterologous expression of bovine pyroglutamyl peptidase type-1 in Escherichia coli: purification, biochemical and kinetic characterisation. Mol Cell Biochem 2006; 297:189-97. [PMID: 17119851 DOI: 10.1007/s11010-006-9346-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Accepted: 09/28/2006] [Indexed: 11/27/2022]
Abstract
We describe the cloning, expression and purification of the bovine XM866409 form of pyroglutamyl peptidase type-1 (PAP1). The cloned nucleotide sequence has an ORF coding for a primary sequence of 209 amino acid residues, which displays 98% identity with the human AJ278828 form of the enzyme. Three amino acid residues at positions 81, 205 and 208 were found to vary between the two sequences. The recombinant bovine PAP1 with a C-terminal His(6) tag (rBtaPAP1(6H)) was expressed in Escherichia coli XL10-Gold cells and purified by immobilised nickel ion affinity chromatography resulting in a yield of 2.6 mg of PAP1 per litre of culture. Purified rBtaPAP1(6H) had a specific activity of 3633 units mg(-1). SDS-PAGE revealed a band for bovine PAP1 with a molecular weight of approximately 24 kDa, which is in good agreement with previously reported data on PAP1. The K (m) and k (cat) values obtained for rBtaPAP1(6H) were 59 muM and 3.5 s(-1), respectively. The optimum pH for activity was 9.0-9.5 and the optimum temperature was 37 degrees C. rBtaPAP1(6H) was found to have an absolute requirement for the thiol-reducing agent DTT, consistent with the expected property of a cysteine protease. Kinetic studies using the peptides pGlu-His-Pro-NH(2) (TRH), pGlu-Ala and pGlu-Val revealed K (i) values of 44.1, 141 and 652.17 microM, respectively. The lowest K (i), observed for Thyrotropin-releasing Hormone (TRH), indicates that rBtaPAP1(6H) has a higher affinity for tripeptides over dipeptides.
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Affiliation(s)
- Zelda Kilbane
- School of Biotechnology, National Centre for Sensor Research, Dublin City University, Dublin 9, Republic of Ireland.
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Schaeffer M, de Miranda A, Mottram JC, Coombs GH. Differentiation of Leishmania major is impaired by over-expression of pyroglutamyl peptidase I. Mol Biochem Parasitol 2006; 150:318-29. [PMID: 17028008 DOI: 10.1016/j.molbiopara.2006.09.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2006] [Revised: 09/06/2006] [Accepted: 09/07/2006] [Indexed: 10/24/2022]
Abstract
Pyroglutamyl peptidases I (PPI) are cysteine peptidases of the clan CF, family C15, which hydrolyse N-terminal l-pyroglutamyl residues (l-pGlu). The l-pGlu modification is a post-transcriptional modification that confers relative aminopeptidase resistance and, in some cases, is essential to the modified peptides' biological activity. PPIs have been identified in a variety of organisms, although definitive biological functions have yet to be attributed to them. The L. major PPI was expressed in Escherichia coli as active recombinant enzyme, and shown to have biochemical properties more similar to mammalian than bacterial PPIs. The LmPPI active site catalytic triad of E101, C210, and H234 was confirmed by mutagenesis. PPI activity was detected in L. major promastigotes, and the enzyme localised to the parasite cytosol. No detectable phenotype could be observed for L. major PPI-deficient mutants, which retained infectivity to macrophages in vitro and mice. However, over-expression of the active PPI, but not inactive PPI(C210A), in L. major impaired differentiation from the procyclic promastigote to the infective metacyclic promastigote. Susceptibility to a natural l-pGlu-modified antimicrobial peptide, gomesin, was tested using the different cell lines, which were all equally susceptible. Whilst PPI is widespread through the eukaryotic kingdom, this study now suggests that the enzyme is not essential for normal eukaryotic cell function. However, PPI could be involved in regulating the action of l-pGlu-modified peptides required for differentiation of L. major.
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Affiliation(s)
- Marie Schaeffer
- Division of Infection & Immunity, Institute of Biomedical and Life Sciences and Wellcome Centre for Molecular Parasitology, Glasgow Biomedical Research Centre, University of Glasgow, Glasgow G12 8TA, Scotland, UK
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38
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Morty RE, Bulau P, Pellé R, Wilk S, Abe K. Pyroglutamyl peptidase type I from Trypanosoma brucei: a new virulence factor from African trypanosomes that de-blocks regulatory peptides in the plasma of infected hosts. Biochem J 2006; 394:635-45. [PMID: 16248854 PMCID: PMC1383713 DOI: 10.1042/bj20051593] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Peptidases of parasitic protozoans are emerging as novel virulence factors and therapeutic targets in parasitic infections. A trypanosome-derived aminopeptidase that exclusively hydrolysed substrates with Glp (pyroglutamic acid) in P1 was purified 9248-fold from the plasma of rats infected with Trypanosoma brucei brucei. The enzyme responsible was cloned from a T. brucei brucei genomic DNA library and identified as type I PGP (pyroglutamyl peptidase), belonging to the C15 family of cysteine peptidases. We showed that PGP is expressed in all life cycle stages of T. brucei brucei and is expressed in four other blood-stream-form African trypanosomes. Trypanosome PGP was optimally active and stable at bloodstream pH, and was insensitive to host plasma cysteine peptidase inhibitors. Native purified and recombinant hyper-expressed trypanosome PGP removed the N-terminal Glp blocking groups from TRH (thyrotrophin-releasing hormone) and GnRH (gonadotropin-releasing hormone) with a k(cat)/K(m) value of 0.5 and 0.1 s(-1) x microM(-1) respectively. The half-life of TRH and GnRH was dramatically reduced in the plasma of trypanosome-infected rats, both in vitro and in vivo. Employing an activity-neutralizing anti-trypanosome PGP antibody, and pyroglutamyl diazomethyl ketone, a specific inhibitor of type I PGP, we demonstrated that trypanosome PGP is entirely responsible for the reduced plasma half-life of TRH, and partially responsible for the reduced plasma half-life of GnRH in a rodent model of African trypanosomiasis. The abnormal degradation of TRH and GnRH, and perhaps other neuropeptides N-terminally blocked with a pyroglutamyl moiety, by trypanosome PGP, may contribute to some of the endocrine lesions observed in African trypanosomiasis.
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Affiliation(s)
- Rory E Morty
- Department of Internal Medicine, University Hospital Giessen and Marburg, Aulweg 123, D-35392 Giessen, Germany.
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Monsuur AJ, Stepniak D, Diosdado B, Wapenaar MC, Mearin ML, Koning F, Wijmenga C. Genetic and functional analysis of pyroglutamyl-peptidase I in coeliac disease. Eur J Gastroenterol Hepatol 2006; 18:637-44. [PMID: 16702853 DOI: 10.1097/00042737-200606000-00010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Coeliac disease (CD) is an enteropathy caused by an immune reaction towards wheat gluten and similar proteins from barley and rye. It was shown that some gluten peptides spontaneously form N-terminal L-pyroglutamate. This modification could potentially make gluten more resistant to proteolytic degradation within the intestine. Pyroglutamyl-peptidase I (PGPEPI) is an enzyme that hydrolytically removes the L-pyroglutamyl residues that render the modified proteins and peptides more sensitive to degradation by other proteases. Interestingly, we found that the PGPEP1 gene is located in a CD susceptibility locus. As an impaired enzyme function caused by genetic alterations might increase the amount of immunogenic gluten peptides, we conducted a comprehensive functional genomics analysis of PGPEP1, including DNA sequencing, genetic association testing, and quantifying RNA expression. We also determined the enzymatic activity of PGPEPI in duodenal biopsies. Our results uniformly indicate that PGPEP1 is not involved in the aetiology and pathology of CD.
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Affiliation(s)
- Alienke J Monsuur
- Complex Genetics Section, DBG-Department of Medical Genetics, University Medical Centre, Utrecht, the Netherlands
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Mori K, Ishikawa K. New deblocking aminopeptidases from Pyrococcus horikoshii. Biosci Biotechnol Biochem 2006; 69:1854-60. [PMID: 16244434 DOI: 10.1271/bbb.69.1854] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
It has been reported that one of the hyperthermostable aminopeptidases from Pyrococcus horikoshii exhibits hydrolytic activity toward short peptides and acyl-peptides (deblocking activity). In the genome database of P. horikoshii, two new open reading frames homologous to the hyperthermostable aminopeptidase of P. horikoshii were found. The two new genes for the proteins were cloned, expressed using E. coli, and characterized. The purified proteins gave a single band on SDS-PAGE corresponding to molecular masses of 42 kDa and 41 kDa respectively, and exhibited aminopeptidase activity, including deblocking activity. These enzymes are likely to exist as oligomeric structures at neutral pH. The optimum pHs of the two enzyme activities were in the range of 7.0 to 7.5, and the optimum temperatures for the activities were around 100 degrees C. The enzymes exhibited low hydrolytic activity for peptide substrates longer than 10 residues. They were activated by cobalt and zinc ions. Their substrate specificities and activation factors are different. It was confirmed that P. horikoshii has three similar aminopeptidases with deblocking activity and that these enzymes appear to play important roles in hydrolyzing small peptides in P. horikoshii cells.
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Affiliation(s)
- Kazushige Mori
- National Institute of Advanced Industrial Science and Technology (AIST Kansai), Ikeda, Osaka, Japan.
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Kelly JA, Scalabrino GA, Slator GR, Cullen AA, Gilmer JF, Lloyd DG, Bennett GW, Bauer K, Tipton KF, Williams CH. Structure-activity studies with high-affinity inhibitors of pyroglutamyl-peptidase II. Biochem J 2005; 389:569-76. [PMID: 15799721 PMCID: PMC1175135 DOI: 10.1042/bj20041722] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Inhibitors of PPII (pyroglutamyl-peptidase II) (EC 3.4.19.6) have potential applications as investigative and therapeutic agents. The rational design of inhibitors is hindered, however, by the lack of an experimental structure for PPII. Previous studies have demonstrated that replacement of histidine in TRH (thyrotropin-releasing hormone) with asparagine produces a competitive PPII inhibitor (Ki 17.5 microM). To gain further insight into which functional groups are significant for inhibitory activity, we investigated the effects on inhibition of structural modifications to Glp-Asn-ProNH2 (pyroglutamyl-asparaginyl-prolineamide). Synthesis and kinetic analysis of a diverse series of carboxamide and C-terminally extended Glp-Asn-ProNH2 analogues were undertaken. Extensive quantitative structure-activity relationships were generated, which indicated that key functionalities in the basic molecular structure of the inhibitors combine in a unique way to cause PPII inhibition. Data from kinetic and molecular modelling studies suggest that hydrogen bonding between the asparagine side chain and PPII may provide a basis for the inhibitory properties of the asparagine-containing peptides. Prolineamide appeared to be important for interaction with the S2' subsite, but some modifications were tolerated. Extension of Glp-Asn-ProNH2 with hydrophobic amino acids at the C-terminus led to a novel set of PPII inhibitors active in vitro at nanomolar concentrations. Such inhibitors were shown to enhance recovery of TRH released from rat brain slices. Glp-Asn-Pro-Tyr-Trp-Trp-7-amido-4-methylcoumarin displayed a Ki of 1 nM, making it the most potent competitive PPII inhibitor described to date. PPII inhibitors with this level of potency should find application in exploring the biological functions of TRH and PPII, and potentially provide a basis for development of novel therapeutics.
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Affiliation(s)
- Julie A Kelly
- Department of Biochemistry, Trinity College Dublin, Dublin 2, Ireland.
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Lou YC, Huang YC, Pan YR, Chen C, Liao YD. Roles of N-terminal pyroglutamate in maintaining structural integrity and pKa values of catalytic histidine residues in bullfrog ribonuclease 3. J Mol Biol 2005; 355:409-21. [PMID: 16309702 DOI: 10.1016/j.jmb.2005.10.069] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2005] [Revised: 10/19/2005] [Accepted: 10/25/2005] [Indexed: 11/22/2022]
Abstract
Many proteins and bioactive peptides contain an N-terminal pyroglutamate residue (Pyr1). This residue reduces the susceptibility of the protein to aminopeptidases and often has important functional roles. The antitumor ribonuclease RC-RNase 3 (RNase 3) from oocytes of Rana catesbeiana (bullfrog) is one such protein. We have produced recombinant RNase 3 containing the N-terminal Pyr1 (pRNase 3) and found it to be indistinguishable from the native RNase 3 by mass spectrometry and a variety of other biochemical and immunological criteria. We demonstrated by NMR analysis that the Pyr1 of pRNase 3 forms hydrogen bonds with Lys9 and Ile96 and stabilizes the N-terminal alpha-helix in a rigid conformation. In contrast, the N-terminal alpha-helix becomes flexible and the pKa values of the catalytic residues His10 and His97 altered when Pyr1 formation is blocked by an extra methionine at the N terminus in the recombinant mqRNase 3. Thus, our results provide a mechanistic explanation on the essential role of Pyr1 in maintaining the structural integrity, especially at the N-terminal alpha-helix, and in providing the proper environment for the ionization of His10 and His97 residues for catalysis and cytotoxicity against HeLa cells.
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Affiliation(s)
- Yuan-Chao Lou
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan, ROC
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Larrinaga G, Callado LF, Agirregoitia N, Varona A, Gil J. Subcellular distribution of membrane-bound aminopeptidases in the human and rat brain. Neurosci Lett 2005; 383:136-40. [PMID: 15936526 DOI: 10.1016/j.neulet.2005.03.061] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Revised: 03/10/2005] [Accepted: 03/30/2005] [Indexed: 11/26/2022]
Abstract
We evaluated the subcellular distribution of four membrane-bound aminopeptidases in the human and rat brain cortex. The particulate enzymes under study--puromycin-sensitive aminopeptidase (PSA), aminopeptidase N (APN), pyroglutamyl-peptidase I (PG I) and aspartyl-aminopeptidase (Asp-AP)--were fluorometrically measured using beta-naphthylamide derivatives. Membrane-bound aminopeptidase activity was found in all the studied subcellular fractions (myelinic, synaptosomal, mitochondrial, microsomal and nuclear fractions), although not homogenously. Human PSA showed highest activity in the microsomal fraction. APN was significantly higher in the nuclear fraction of both species, while PG I showed highest activity in the synaptosomal and myelinic fractions of the human and rat brain. The present results suggest that in addition to inactivating neuropeptides at the synaptic cleft, these enzymes may participate in other physiological processes. Moreover, these peptidases may play specific roles depending on their activity levels at the different subcellular structures where they are localized.
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Affiliation(s)
- Gorka Larrinaga
- Department of Nursing I, University of the Basque Country, Bilbao, Bizkaia, Spain.
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Olivo RDA, Teixeira CDFP, Silveira PF. Representative aminopeptidases and prolyl endopeptidase from murine macrophages: Comparative activity levels in resident and elicited cells. Biochem Pharmacol 2005; 69:1441-50. [PMID: 15857608 DOI: 10.1016/j.bcp.2005.03.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2004] [Accepted: 03/04/2005] [Indexed: 11/30/2022]
Abstract
Macrophages are considered the main effector cells of immune system. Under stimulation these cells are known to be activated by a process involving morphological, biochemical and functional changes. Since altered peptidase activities could be among the factors leading to the differentiation and activation of these cells, in the present work seven naphthylamide derivative substrates were employed to assess representative aminopeptidase and prolyl endopeptidase activities in resident and elicited macrophages of mice. Soluble basic aminopeptidase and prolyl endopeptidase and soluble and particulate neutral and prolyl dipeptidyl aminopeptidase IV activities were present at measurable levels while particulate prolyl endopeptidase and basic aminopeptidase, and particulate and soluble cystyl and pyroglutamyl aminopeptidases were not detectable. Kinetic parameters, chloride activation and the inhibitory effects of puromycin, bestatin, amastatin and diprotin A characterized differential properties of these peptidase activities. The observed increment (about 6-17-fold) of the soluble basic aminopeptidase and prolyl endopeptidase and soluble and particulate neutral and prolyl dipeptidyl aminopeptidase IV activities in elicited macrophages was particularly relevant, as these might contribute to an increased ability of this cell to inactivate several susceptible substrates known to be inflammatory and/or immunological mediators.
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Affiliation(s)
- Renata do Amaral Olivo
- Laboratory of Pharmacology, Instituto Butantan, Av. Dr.Vital Brazil, 1500-CEP, 05503-900 São Paulo, SP, Brazil
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Supuran CT, Scozzafava A, Mastrolorenzo A. Bacterial proteases: current therapeutic use and future prospects for the development of new antibiotics. Expert Opin Ther Pat 2005. [DOI: 10.1517/13543776.11.2.221] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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Ezura Y, Kajita M, Ishida R, Yoshida S, Yoshida H, Suzuki T, Hosoi T, Inoue S, Shiraki M, Orimo H, Emi M. Association of multiple nucleotide variations in the pituitary glutaminyl cyclase gene (QPCT) with low radial BMD in adult women. J Bone Miner Res 2004; 19:1296-301. [PMID: 15231017 DOI: 10.1359/jbmr.040324] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2003] [Revised: 02/27/2004] [Accepted: 03/29/2004] [Indexed: 11/18/2022]
Abstract
UNLABELLED Correlation between 13 genetic variations of the glutaminyl-peptide cyclotransferase gene and adjusted aBMD was tested among 384 adult women. Among 13 variations with strong linkage disequilibrium, R54W showed a prominent association (p = 0.0003), which was more striking when examined among 309 elder subjects (> or =50 years; p = 0.0001). Contribution for postmenopausal bone loss was suggested. INTRODUCTION Alterations in homeostatic regulation of estrogen through the hypothalamus-pituitary-gonadal axis (HPG axis) importantly affect the pathogenesis of osteoporosis. Osteoporosis-susceptibility genes have been proposed in this hormonal axis, such as estrogen receptor genes and the gonadotropin-releasing hormone gene (GnRH). Here we report another example of genes: glutaminyl-peptide cyclotransferase gene (QPCT), an essential modifier of pituitary peptide hormones, including GnRH. MATERIALS AND METHODS Analyses of association of 13 single nucleotide polymorphisms (SNPs) at the QPCT locus with adjusted areal BMD (adj-aBMD) were carried out among 384 adult women. Linkage disequilibrium (LD) was analyzed by haplotype estimation and calculation of D' and r2. Multiple regression analysis was applied for evaluating the combined effects of the variations. RESULTS AND CONCLUSIONS LD analysis indicated strong linkage disequilibrium within the entire 30-kb region of the QPCT gene. Significant correlations were observed between the genotypes of the six SNPs and the radial adj-aBMD, among which R54W (nt + 160C>T) presented the most prominent association (p = 0.0003). Striking association was observed for these SNPs among the 309 subjects >50 years of age (R54W, p = 0.0001; -1095T>C, p = 0.0002; -1844C>T, p = 0.0002). Multiple regression analyses indicated that multiple SNPs in the gene might act in combination to determine the radial adj-aBMD. These results indicate that genetic variations in QPCT are the important factors affecting the BMD of adult women that contribute to susceptibility for osteoporosis. The data should provide new insight into the etiology of the disease and may suggest a new target to be considered during treatment.
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Affiliation(s)
- Yoichi Ezura
- Department of Molecular Biology, Institute of Gerontology, Nippon Medical School, Kawasaki, Japan
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Abe K, Watanabe N, Kosaka T, Yamada M, Tokui T, Ikeda T. Hydrolysis of synthetic substrate, L-pyroglutamyl p-nitroanilide is catalyzed solely by pyroglutamyl aminopeptidase I in rat liver cytosol. Biol Pharm Bull 2004; 26:1528-33. [PMID: 14600395 DOI: 10.1248/bpb.26.1528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Pyroglutamyl aminopeptidase I (PAP-I) is a cytosolic cysteine peptidase, which hydrolytically removes the L-pyroglutamate residue from the amino terminus of endogenous proteins and peptides. L-Pyroglutamyl p-nitroanilide serves as the synthetic substrate of this enzyme, while there is a possibility of other hydrolases being involved in the hydrolysis of this xenobiotic substrate. We cloned a full-length cDNA encoding rat PAP-I from a rat liver cDNA library and expressed this cDNA in Escherichia coli to obtain a recombinant PAP-I as a single protein. The cDNA encoded a sequence of 209 amino acids with a calculated molecular weight of 22913 Da. The homology of the deduced amino acid sequence of rat PAP-I was 98.6 and 94.3% to mouse and human PAP-Is, respectively. The biochemical properties of the recombinant rat PAP-I were almost identical to those of the recombinant mouse and human PAP-Is and the purified rat liver cytosolic PAP-I in terms of the molecular weight, subunit structure, affinity to the substrate, inhibitor profile and pH optimum. Immunoblot analysis using an antibody raised against recombinant rat PAP-I showed that rat PAP-I is present almost exclusively in the cytosolic fraction of the rat liver. Moreover, the hydrolyzing activity for L-pyroglutamyl p-nitroanilide in rat liver cytosolic fraction was completely inhibited by the antibody, strongly suggesting that this xenobiotic substrate is hydrolyzed solely by PAP-I.
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Affiliation(s)
- Koji Abe
- Pharmacokinetics and Drug Delivery Research Laboratories, Sankyo Co., Ltd., Hiromachi, Tokyo 140-8710, Japan.
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Ribó M, Bosch M, Torrent G, Benito A, Beaumelle B, Vilanova M. Quantitative analysis, using MALDI-TOF mass spectrometry, of the N-terminal hydrolysis and cyclization reactions of the activation process of onconase. ACTA ACUST UNITED AC 2004; 271:1163-71. [PMID: 15009195 DOI: 10.1111/j.1432-1033.2004.04020.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Onconase, a member of the ribonuclease superfamily, is a potent cytotoxic agent that is undergoing phase II/III human clinical trials as an antitumor drug. Native onconase from Rana pipiens and its amphibian homologs have an N-terminal pyroglutamyl residue that is essential for obtaining fully active enzymes with their full potential as cytotoxins. When expressed cytosolically in bacteria, Onconase is isolated with an additional methionyl (Met1) residue and glutaminyl instead of a pyroglutamyl residue at position 1 of the N-terminus and is consequently inactivated. The two reactions necessary for generating the pyroglutamyl residue have been monitored by MALDI-TOF MS. Results show that hydrolysis of Met(-1), catalyzed by Aeromonas aminopeptidase, is optimal at a concentration of >or= 3 m guanidinium-chloride, and at pH 8.0. The intramolecular cyclization of glutaminyl that renders the pyroglutamyl residue is not accelerated by increasing the concentration of denaturing agent or by strong acid or basic conditions. However, temperature clearly accelerates the formation of pyroglutamyl. Taken together, these results have allowed the characterization and optimization of the onconase activation process. This procedure may have more general applicability in optimizing the removal of undesirable N-terminal methionyl residues from recombinant proteins overexpressed in bacteria and providing them with biological and catalytic properties identical to those of the natural enzyme.
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Affiliation(s)
- Marc Ribó
- Laboratori d'Enginyeria de Proteïnes, Departament de Biologia, Facultat de Ciències, Universitat de Girona, Girona, Spain
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Pekary AE, Sattin A, Meyerhoff JL, Chilingar M. Valproate modulates TRH receptor, TRH and TRH-like peptide levels in rat brain. Peptides 2004; 25:647-58. [PMID: 15165721 DOI: 10.1016/j.peptides.2004.01.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2003] [Accepted: 01/27/2004] [Indexed: 01/01/2023]
Abstract
We have tested our hypothesis that alterations in the levels of TRH receptors, and the synthesis and release of tripeptide TRH, and other neurotropic TRH-like peptides mediate some of the mood stabilizing effects of valproate (Valp). We have directly compared the effect of 1 week of feeding two major mood stabilizers, Valp and lithium chloride (LiCl) on TRH binding in limbic and extra-limbic regions of male WKY rats. Valp increased TRH receptor levels in nucleus accumbens and frontal cortex. Li increased TRH receptor binding in amygdala, posterior cortex and cerebellum. The acute, chronic and withdrawal effects of Valp on brain levels of TRH (pGlu-His-Pro-NH2, His-TRH) and five other TRH-like peptides, Glu-TRH, Val-TRH, Tyr-TRH, Leu-TRH and Phe-TRH were measured by combined HPLC and RIA. Acute treatment increased TRH and TRH-like peptide levels within most brain regions, most strikingly in pyriform cortex. The fold increases (in parentheses) were: Val-TRH (58), Phe-TRH (54), Tyr-TRH (25), TRH (9), Glu-TRH (4) and Leu-TRH (3). We conclude that the mood stabilizing effects of Valp may be due, at least in part, to its ability to alter TRH and TRH-like peptide, and TRH receptor levels in the limbic system and other brain regions implicated in mood regulation and behavior.
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Affiliation(s)
- A Eugene Pekary
- Research Services, West Los Angeles Va Medical Center, CA 90073, USA.
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Abe K, Fukuda K, Tokui T. Marginal Involvement of Pyroglutamyl Aminopeptidase I in Metabolism of Thyrotropin-Releasing Hormone in Rat Brain. Biol Pharm Bull 2004; 27:1197-201. [PMID: 15305021 DOI: 10.1248/bpb.27.1197] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
On thyrotropin-releasing hormone (TRH) metabolism, pyroglutamyl aminopeptidase II (PAP-II), a zinc-dependent ectoenzyme primarily located in the central nervous system, is believed to play a predominant role. Recently we cloned pyroglutamyl aminopeptidase I (PAP-I) which is known for specifically removing a L-pyroglutamate (L-pGlu) residue from the amino terminus of proteins and peptides including TRH. To investigate possible contribution of PAP-I toward TRH metabolism, we conducted biochemical and immunohistochemical characterization using recombinant rat, mouse and human PAP-Is and an antibody raised against rat PAP-I. The Km values toward TRH by the recombinant PAP-Is were about 0.05 mM, being similar value to the reported value of recombinant PAP-II. The L-pGlu-cleaving activities toward TRH in rat brain homogenate were inhibited by a PAP-II specific inhibitor 1,10-phenanthroline, but not inhibited by the antibody against rat PAP-I. Immunohistochemical study in rats revealed heterogeneous distribution of PAP-I in the pituitary, the target tissue of TRH, but the distribution was cytosolic. Taken together, these results suggested that PAP-I might not be dominantly involved in the degradation of TRH in rats. Additionally, we found that PAP-I was localized in the renal proximal tubules. Further investigations are needed for elucidating the function of PAP-I in these restricted sites.
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Affiliation(s)
- Koji Abe
- Drug Metabolism and Pharmacokinetics Research Laboratories, Sankyo Co., Ltd, Tokyo, Japan.
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