DOCSLIB.ORG

Structure Elucidation and Biosynthetic Enzyme Characterization of Bacteriocins by Jeella Zara Acedo a Thesis Submitted in Partia

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Structure Elucidation and Biosynthetic Enzyme Characterization of Bacteriocins by Jeella Zara Acedo a Thesis Submitted in Partia Structure Elucidation and Biosynthetic Enzyme Characterization of Bacteriocins by Jeella Zara Acedo A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Chemistry University of Alberta © Jeella Zara Acedo, 2017 Abstract Acidocin B (AcdB), a bacteriocin from Lactobacillus acidophilus M46 that was initially reported to be a linear peptide, was purified and shown to be circular based on MALDI-TOF MS and MS/MS sequencing. MS analysis further revealed that AcdB is comprised of 58 amino acid residues, instead of 59 residues as initially reported. The NMR solution structure of AcdB in sodium dodecyl sulfate micelles was solved, revealing that AcdB consists of four !-helices that are folded to form a globular bundle with a central pore. This is the first reported three-dimensional structure (3D) for a subgroup II circular bacteriocin. Comparison of the structure of AcdB to that of carnocyclin A, a subgroup I circular bacteriocin, highlighted the differences between the two subgroups. At least seven putative subgroup II circular bacteriocins were identified using BLAST, and sequence analysis revealed a highly conserved asparagine residue at the leader peptide cleavage sites, suggesting that an asparagine endopeptidase might be involved in their biosynthesis. Lastly, the biosynthetic gene cluster of AcdB was sequenced and characterized. Lacticin Q (LnqQ) and aureocin A53 (AucA) are leaderless bacteriocins (class IIc) from Lactococcus lactis QU 5 and Staphylococcus aureus A53, respectively. Their 3D NMR solution structures were determined, revealing that both peptides are composed of four !-helices that assume a saposin-like fold with a highly cationic surface and a hydrophobic core. The observed structural motif is remarkably similar to the overall fold of the two-component leaderless bacteriocins, enterocin 7A and 7B. Homology modeling showed that the aforementioned motif may be shared among broad-spectrum leaderless bacteriocins despite the variations in their sequence identities and lengths. The structures ii of LnqQ and AucA were also demonstrated to exhibit certain similarities to those of the circular bacteriocins. Activity assays showed that the two peptides, LnqQ and AucA, combined do not act synergistically and have different antimicrobial spectra and potency, suggesting that sequence disparities play a vital role in their modes of action. Carnobacteriocin X (CbnX) was originally reported as a single-peptide bacteriocin (class IId). However, sequence analysis and synergy assays revealed that CbnX belongs to a two-peptide bacteriocin (class IIb), with CbnY as its partner. CbnXY is the first two- peptide bacteriocin reported in carnobacteria. CbnX and CbnY are inactive individually, but elicit synergistic activity against closely related strains when combined. The NMR solution structures of CbnX and CbnY were elucidated and shown to strongly resemble the structures of other class IIb bacteriocins (i.e. LcnG, PlnEF, PlnJK). CbnX consists of an extended, amphipathic !-helix and a flexible C-terminus. CbnY has two !-helices (one hydrophobic, one amphipathic) connected by a short loop, and a cationic C-terminus. Binding studies showed that CbnX and CbnY do not interact directly, suggesting that a membrane-bound receptor may be required to mediate the formation of the CbnXY complex. Pneumococcin is a two-component lantibiotic, comprised of PneA1 and PneA2, from Streptococcus pneumoniae R6. Its biosynthetic machinery encodes a putative flavin- dependent reductase, named PneJB, which is likely involved in the formation of D-Ala and D-Abu. The activity of PneJB was investigated through the heterologous expression of pneumococcin biosynthetic proteins in Escherichia coli. Coexpression of the precursor peptides (PneA1 and PneA2) and the lantibiotic synthetase (PneM) with and without PneJB produced a mixture of partially modified substrates that could not be separated by iii RP-HPLC. To potentially address this issue, truncated precursor peptides were designed and cloned. The truncated peptides, however, could not be successfully expressed in E. coli. Hence, chemical synthesis of substrate analogues is currently being pursued. Other approaches to obtain the precursor peptides are presented herein. The PneJB enzyme was expressed and purified as a SUMO fusion protein, wherein the SUMO tag could be readily cleaved. The substrate analogues and the PneJB enzyme will consequently be used for in vitro PneJB activity assays and future crystallization trials. iv Preface The content of Chapter 2 was published as Acedo et al. Appl. Environ. Microbiol. 2015, 81, 2910-2918. I performed all the experiments with assistance from the other authors, specifically in the sequencing of the AcdB biosynthetic gene cluster and acquisition of NMR spectroscopic data. I wrote the manuscript except for the section on the gene cluster. Studies described in Chapter 3 were published as Acedo et al. Biochemistry. 2016, 55, 4798-4806. I performed all the experiments with assistance from the other authors, specifically in the cloning of the expression plasmids, acquisition of NMR spectroscopic data, and activity assays. I wrote the manuscript. The studies in Chapter 4 were published as Acedo et al. FEBS Lett. 2017, 591, 1349- 1459. I performed the circular dichroism experiments, expression and purification of [13C,15N]-CbnX and CbnY, and the elucidation of their NMR solution structures. The other authors performed the activity assays, cloning of expression plasmids, binding studies, and assisted with the acquisition of NMR spectroscopic data. I performed approximately 75% of the work and assisted in writing the manuscript. Chapter 5 is an unpublished work. I performed all the experiments described in this chapter. v Acknowledgements This thesis would not have been possible without the help, guidance, and support of several individuals. First and foremost, I am beyond grateful to my supervisor, Prof. John C. Vederas, for giving me the opportunity to do research in his lab. His insights, constant support, and encouragement kept me moving forward and honed my skills as a researcher. The lab environment and resources provided in the Vederas group have been ideal for learning and professional growth. I am thankful to all the people I worked with in the various projects presented in this thesis. I am also very grateful to the exceptional support staff members in the Department of Chemistry who are among the kindest and most approachable people I have worked with. In particular, I would like to thank Mark Miskolzie and Dr. Ryan McKay of the NMR facility, Jing Zheng, Dr. Randy Whittal and Bela Reiz of the MS facility, Wayne Moffat of the Analytical Instrumentation laboratory, and Gareth Lambkin of the Biological Services laboratory. I am also grateful to Pascal Mercier of NANUC for his help in CYANA. I am thankful to Dr. Marco van Belkum, Dr. Conrad Fischer, and Sorina Chiorean for proofreading this thesis, and all their inputs in improving this manuscript. I am thankful to the Alberta Innovates Health Solutions and the University of Alberta for funding my graduate studies. I also would like to acknowledge special people who have been instrumental not only in the completion of this thesis, but also in the success of my graduate studies as a whole. On top of my thank you list is Dr. Marco van Belkum, who has been my mentor since day one. I am extremely grateful for all the things that you taught me, and it was much pleasure working with you. I am thankful to Dr. Christopher Lohans, who also helped me start up in the lab, and has since been a constant source of advice. Thank you vi Chris for unselfishly sharing your time and ideas. To Dr. Shaun McKinnie, thank you for being supportive throughout my graduate studies. I found your inputs in my seminars, scholarship applications, and random research questions very helpful. You and Chris have been inspirational and I look up to both of you for your character and brilliance. To Dr. Kaitlyn Towle, thank you for always being willing to help and for all our fruitful discussions. To Dr. Leah Martin-Visscher, thank you for always being reachable by e-mail to answer my NMR questions, and for dropping by the lab whenever we need help. You have been a very good teacher. To Albert Remus, thank you for assisting with genome work and answering all my genome-related questions. It was wonderful having to work with you. To Randy Sanichar, thank you for being my go-to person for my organic chemistry questions and for being a good friend. To everyone in the Vederas group who offered me advice and assistance at certain points during the last five years, and with whom I have shared some good times with, thank you very much! I am also extremely grateful to my family and friends for the encouragement and support. To my parents, thank you for all your sacrifices, love, and support that paved the way to several amazing opportunities for me, and led me to where I am today. To my husband, Kristian, words are not enough to say how grateful I am to have gone through grad school with you. As a research-partner, you have been an endless source of ideas and your passion for research is inspiring. As a life-partner, your love and support are definitely unmatched. Above all, I am grateful to God for the gift of life and for bringing good people along the way throughout this journey. To God be the glory! vii Table of Contents Chapter 1 ......................................................................................................
Load more

Recommended publications
  • Examples of Successful Protein Expression with SUMO Reference Protein Type Family Kda System (Pubmed ID)
    Examples of Successful Protein Expression with SUMO Reference Protein Type Family kDa System (PubMed ID) 23 (FGF23), human Growth factor FGF superfamily ~26 E. coli 22249723 SARS coronavirus (SARS-CoV) membrane 3C-like (3CL) protease Viral membrane protein protein 33.8 E. coli 16211506 5′nucleotidase-related apyrase (5′Nuc) Saliva protein (apyrase) 5′nucleotidase-related proteins 65 E. coli 20351782 Acetyl-CoA carboxylase 1 (ACC1) Cytosolic enzyme Family of five biotin-dependent carboxylases ~7 E. coli 22123817 Acetyl-CoA carboxylase 2 (ACC2) BCCP domain Cytosolic enzyme Family of five biotin-dependent carboxylases ~7 E. coli 22123817 Actinohivin (AH) Lectin Anti-HIV lectin of CBM family 13 12.5 E. coli DTIC Allium sativum leaf agglutinin (ASAL) Sugar-binding protein Mannose-binding lectins 25 E. coli 20100526 Extracellular matrix Anosmin protein Marix protein 100 Mammalian 22898776 Antibacterial peptide CM4 (ABP-CM4) Antibacterial peptide Cecropin family of antimicrobial peptides 3.8 E. coli 19582446 peptide from centipede venoms of Scolopendra Antimicrobial peptide scolopin 1 (AMP-scolopin 1) small cationic peptide subspinipes mutilans 2.6 E. coli 24145284 Antitumor-analgesic Antitumor-analgesic peptide (AGAP) peptide Multifunction scorpion peptide 7 E. coli 20945481 Anti-VEGF165 single-chain variable fragment (scFv) Antibody Small antibody-engineered antibody 30 E. coli 18795288 APRIL TNF receptor ligand tumor necrosis factor (TNF) ligand 16 E. coli 24412409 APRIL (A proliferation-inducing ligand, also named TALL- Type II transmembrane 2, TRDL-1 and TNFSF-13a) protein Tumor necrosis factor (TNF) family 27.51 E. coli 22387304 Aprotinin/Basic pancreatic trypsin inhibitor (BPTI) Inhibitor Kunitz-type inhibitor 6.5 E.
    [Show full text]
  • Harnessing the Power of Bacteria in Advancing Cancer Treatment
    International Journal of Molecular Sciences Review Microbes as Medicines: Harnessing the Power of Bacteria in Advancing Cancer Treatment Shruti S. Sawant, Suyash M. Patil, Vivek Gupta and Nitesh K. Kunda * Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John’s University, Jamaica, NY 11439, USA; [email protected] (S.S.S.); [email protected] (S.M.P.); [email protected] (V.G.) * Correspondence: [email protected]; Tel.: +1-718-990-1632 Received: 20 September 2020; Accepted: 11 October 2020; Published: 14 October 2020 Abstract: Conventional anti-cancer therapy involves the use of chemical chemotherapeutics and radiation and are often non-specific in action. The development of drug resistance and the inability of the drug to penetrate the tumor cells has been a major pitfall in current treatment. This has led to the investigation of alternative anti-tumor therapeutics possessing greater specificity and efficacy. There is a significant interest in exploring the use of microbes as potential anti-cancer medicines. The inherent tropism of the bacteria for hypoxic tumor environment and its ability to be genetically engineered as a vector for gene and drug therapy has led to the development of bacteria as a potential weapon against cancer. In this review, we will introduce bacterial anti-cancer therapy with an emphasis on the various mechanisms involved in tumor targeting and tumor suppression. The bacteriotherapy approaches in conjunction with the conventional cancer therapy can be effective in designing novel cancer therapies. We focus on the current progress achieved in bacterial cancer therapies that show potential in advancing existing cancer treatment options and help attain positive clinical outcomes with minimal systemic side-effects.
    [Show full text]
  • Processing of Progranulin Into Granulins Involves Multiple Lysosomal Proteases and Is Affected in Frontotemporal Lobar Degeneration
    Processing of progranulin into granulins involves multiple lysosomal proteases and is affected in frontotemporal lobar degeneration Swetha Mohan University of California San Francisco Paul J. Sampognaro University of California San Francisco Andrea R. Argouarch University of California San Francisco Jason C. Maynard University of California San Francisco Anand Patwardhan University of California San Francisco Emma C. Courtney University of California San Francisco Amanda Mason University of California San Francisco Kathy H. Li University of California San Francisco William W. Seeley University of California San Francisco Bruce L. Miller University of California San Francisco Alma Burlingame University of California San Francisco Mathew P. Jacobson University of California San Francisco Aimee Kao ( [email protected] ) University of California San Francisco https://orcid.org/0000-0002-7686-7968 Research article Keywords: Progranulin, granulin, frontotemporal lobar degeneration, lysosome, protease, pH, asparagine endopeptidase Page 1/31 Posted Date: July 29th, 2020 DOI: https://doi.org/10.21203/rs.3.rs-44128/v2 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Version of Record: A version of this preprint was published at Molecular Neurodegeneration on August 3rd, 2021. See the published version at https://doi.org/10.1186/s13024-021-00472-1. Page 2/31 Abstract Background - Progranulin loss-of-function mutations are linked to frontotemporal lobar degeneration with TDP-43 positive inclusions (FTLD-TDP-Pgrn). Progranulin (PGRN) is an intracellular and secreted pro- protein that is proteolytically cleaved into individual granulin peptides, which are increasingly thought to contribute to FTLD-TDP-Pgrn disease pathophysiology. Intracellular PGRN is processed into granulins in the endo-lysosomal compartments.
    [Show full text]
  • Molecular Analysis of Candidate Probiotic Effector Molecules of Lactobacillus Plantarum
    Molecular analysis of candidate probiotic effector molecules of Lactobacillus plantarum Daniela Maria Remus Thesis committee Promoter Prof. dr. Michiel Kleerebezem Professor of Bacterial Metagenomics Wageningen University Co-promoter Dr. Peter A. Bron Senior Scientist, NIZO food research BV, Ede Other members Prof. dr. Tjakko Abee, Wageningen University Prof. dr. Pascal Hols, University of Lovain (Lovain la Neuve), Belgium Dr. Philippe Langella, National Institute of Agricultural Research (INRA), Paris, France Prof. dr. Roland J. Siezen, Radboud University, Nijmegen This research was conducted under the auspices of the Graduate School VLAG (Advanced studies in Food Technology, Agrobiotechnology, Nutrition and Health Sciences). Molecular analysis of candidate probiotic effector molecules of Lactobacillus plantarum Daniela Maria Remus Thesis submitted in fulfillment of the requirements for the degree of doctor at Wageningen University by the authority of the Rector Magnificus Prof. dr. M.J. Kropff, in the presence of the Thesis Committee appointed by the Academic Board to be defended in public on Tuesday 09 October 2012 at 4 p.m. in the Aula. Daniela Maria Remus Molecular analysis of candidate probiotic effector molecules of Lactobacillus plantarum Ph.D. Thesis, Wageningen University, Wageningen, The Netherlands (2012) With references and summaries in English and Dutch. ISBN 978-94-6173-373-3 Summary Lactobacilli occupy diverse natural habitats, including dairy products and the mammalian gastrointestinal (GI) tract, and several Lactobacillus strains are marketed as probiotics that can interact with host cells in the GI tract by which they are proposed to beneficially influence the health status of their consumers. The discovery of probiotic effector molecules is instrumental to understand the exact modes of probiotic action, which is required for their controlled, safe, and purpose-directed application.
    [Show full text]
  • Plantaricin KW30
    The Molecular and Cellular Characterisation of the First Glycocin: Plantaricin KW30 Judith Stepper 2009 The Molecular and Cellular Characterisation of the First Glycocin: Plantaricin KW30 A thesis presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biochemistry at Massey University, Palmerston North, New Zealand Judith Stepper 2009 “What we know is a drop. What we don’t know is an ocean.” Isaac Newton (1643 – 1727) ABSTRACT Bacteriocins, typically secreted by Gram-positive and -negative bacteria, are ribosomally- synthesised antimicrobial peptides which inhibit the growth of competing bacteria. We have purified a 43 amino acid bacteriocin, plantaricin KW30 (PlnKW30) produced by Lactobacillus plantarum KW30, that has little amino acid sequence similarity to any other characterised bacteriocin. The gene encoding plnKW30 is in a cluster with the genes required for maturation and export of, and immunity to, the bacteriocin. This arrangement of genes is similar to the genomic context of bacteriocin genes in other lactic acid bacteria. The plnKW30 gene cluster comprises six genes encoding a glycosyltransferase, a proteolytic ABC-transporter, two putative thioredoxins, a response regulator and PlnKW30 itself. PlnKW30 was found to possess two unusual post-translational modifications: an O-glycosylated serine and an unprecedented S-glycosylation of the C-terminal cysteine. The modified serine is located on an eight residue loop that is tethered by a disulfide bridge. Both modifications have been identified as N-acetylglucosamines (GlcNAc), making PlnKW30 the first described class IV bacteriocin. A post-translational modification with S-linked GlcNAc is unprecedented in bacteriocins as well as in all genera.
    [Show full text]
  • The Bacteriostatic Diglycocylated Bacteriocin Glycocin F Targets A
    Copyright is owned by the Author of the thesis. Permission is given for a copy to be downloaded by an individual for the purpose of research and private study only. The thesis may not be reproduced elsewhere without the permission of the Author. The Bacteriostatic Diglycosylated Bacteriocin Glycocin F Targets a Sugar-Specific Transporter A thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University, Manawatu New Zealand Kelvin Ross Drower 2014 Dedicated to Nana and Pop Abstract The increasing prevalence of antibiotic-resistance bacteria is threatening to end the antibiotic era established following Alexander Fleming's discovery of penicillin in 1928. Over-prescription and misuse of broad-spectrum antibiotics has hastened the development and spread of antibiotic resistance. This, combined with a lack of research and development (R&D) of new antibiotics by major pharmaceutical companies, may lead to a widespread recurrence of 'incurable' bacterial diseases. However while commercial R&D of antibiotics has waned, much research has been carried out to characterise bacteriocins, ribosomally-synthesised antimicrobial polypeptides thought to be produced by virtually all prokaryotes. Although hundreds of bacteriocins have been identified and characterised, only a handful of their cognate receptors on susceptible cells have been identified. Glycocin F is a bacteriostatic diglycosylated 43-amino acid bacteriocin produced by the Gram-positive bacterium Lactobacillus plantarum KW30 that inhibits the growth of a broad range of bacteria. The mechanism of action of glycocin F is unknown, however evidence suggested that glycocin F binds to cells via a N-acetylglucosamine (GlcNAc) specific phosphoenolpyruvate:carbohydrate-phosphotransferase system (PTS) transporter, as had been shown for lactococcin A, lactococcin B and microcin E492 that target a mannose specific PTS transporter.
    [Show full text]
  • UC Berkeley Electronic Theses and Dissertations
    UC Berkeley UC Berkeley Electronic Theses and Dissertations Title Interactions of Microbes in Communities Permalink https://escholarship.org/uc/item/2hg5h7k6 Author Sczesnak, Andrew Publication Date 2018 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California Interactions of Microbes in Communities By Andrew Sczesnak A dissertation submitted in partial satisfaction of the requirements for the degree of Joint Doctor of Philosophy with University of California, San Francisco in Bioengineering in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Adam P. Arkin, Chair Professor Matthew Traxler Professor Michael Fischbach Fall 2018 Abstract Interactions of Microbes in Communities By Andrew Sczesnak Joint Doctor of Philosophy with University of California, San Francisco in Bioengineering University of California, Berkeley Professor Adam P. Arkin, Chair Groups of microorganisms sharing an environment (microbial communities) are ubiquitous in nature. Microbial communities provide essential ecosystem services to other life on Earth by e.g., participating in global biogeochemical processes or interacting with a host’s immune system. Such microbes compete for scarce resources, modify an environment for their own purposes, actively war, and occasionally cooperate. Though numerous studies have surveyed the diversity of microbial life in different environments, few have determined the ways in which members of microbial communities interact with one another. Understanding the ways and means by which microbes interact is essential if we are to understand how microbial communities form, persist, and change over time. Knowledge of these processes will allow us to rationally design microbial communities to perform useful functions and predict how our actions might shift the balance of microbes in a community, and thus affect its function.
    [Show full text]
  • Produced by Bacillus Amylo- Liquefaciens Isolated From
    RESEARCH ARTICLE INTERNATIONAL MICROBIOLOGY (2006) 9:111-118 www.im.microbios.org Márcia P. Lisboa1 Characterization of a Diego Bonatto2 Delmar Bizani1 bacteriocin-like substance João A.P. Henriques3 produced by Bacillus amylo- Adriano Brandelli1* liquefaciens isolated from 1Department of Science Food, the Brazilian Atlantic forest ICTA, Federal University of Rio Grande do Sul, Porto Alegre, Brazil 2Biotechnology Institute, University of Caxias do Sul, Brazil 3Biotechnology Center, Federal University of Rio Grande do Sul, Summary. A Bacillus strain producing a bacteriocin-like substance was charac- Porto Alegre, Brazil terized by biochemical profiling and 16S rDNA sequencing. Phylogenetic analysis indicated that the strain has high sequence similarity with Bacillus amyloliquefa- ciens. The antimicrobial substance was inhibitory to pathogenic and food-spoilage bacteria, such as Listeria monocytogenes, Bacillus cereus, Serratia marcescens, and Pasteurella haemolytica. It was stable over a wide temperature range, but lost activity when the temperature reached 121°C/15 min. Maximum activity was observed at acidic and neutral pH values, but not at alkaline pH. The antimicrobial Received 18 February 2006 substance was sensitive to the proteolytic action of trypsin, papain, proteinase K, Accepted 17 May 2006 and pronase E. Except for iturins, other antimicrobial peptides have not been des- *Corresponding author: cribed for B. amyloliquefaciens. The identification of a bacteriocin-like inhibitory A. Brandelli substance active against L. monocytogenes addresses an important aspect of food ICTA-UFRGS protection. [Int Microbiol 2006; 9(2):111-118] Av. Bento Gonçalves 9500 91501-970 Porto Alegre, Brazil Tel. +55-5133166249 Fax +55-5133167048 Key words: Bacillus amyloliquefaciens · antimicrobial activity · bacteriocin · E-mail: [email protected] bioactive peptide many attempts are being made to incorporate bacteriocins Introduction into processes and products [25].
    [Show full text]
  • Esomeprazole Inhibits the Lysosomal Cysteine Protease Legumain to Prevent Cancer Metastasis
    Investigational New Drugs https://doi.org/10.1007/s10637-020-01011-3 PRECLINICAL STUDIES Esomeprazole inhibits the lysosomal cysteine protease legumain to prevent cancer metastasis Tian Zhao1 & Yujie Liu1 & Yanfei Hao1 & Wei Zhang1 & Li Tao1 & Dong Wang1 & Yuyin Li1 & Zhenxing Liu1 & Edward A McKenzie2 & Qing Zhao1 & Aipo Diao1 Received: 17 August 2020 /Accepted: 21 September 2020 # Springer Science+Business Media, LLC, part of Springer Nature 2020 Summary Legumain is a newly discovered lysosomal cysteine protease that can cleave asparagine bonds and plays crucial roles in regulating immunity and cancer metastasis. Legumain has been shown to be highly expressed in various solid tumors, within the tumor microenvironment and its levels are directly related to tumor metastasis and poor prognosis. Therefore, legumain presents as a potential cancer therapeutic drug target. In this study, we have identified esomeprazole and omeprazole as novel legumain small molecule inhibitors by screening an FDA approved-drug library. These compounds inhibited enzyme activity of both recombinant and endog- enous legumain proteins with esomeprazole displaying the highest inhibitory effect. Further molecular docking analysis also indicated that esomeprazole, the S- form of omeprazole had the most stable binding to legumain protein compared to R-omeprazole. Transwell assay data showed that esomeprazole and omeprazole reduced MDA-MB-231 breast cancer cell invasion without effecting cell viability. Moreover, an in vivo orthotopic transplantation nude mouse model study showed that esomeprazole reduced lung metastasis of MDA-MB-231 breast cancer cells. These results indicated that esomeprazole has the exciting potential to be used in anti-cancer therapy by preventing cancer metastasis via the inhibition of legumain enzyme activity.
    [Show full text]
  • The Role of Bacteriocins in the Controlling of Foodborne Pathogens
    Indo American Journal of Pharmaceutical Research, 2017 ISSN NO: 2231-6876 THE ROLE OF BACTERIOCINS IN THE CONTROLLING OF FOODBORNE PATHOGENS Abdulhakim Abamecha Department of Biomedical Sciences, Faculty of Public Health and Medical Sciences, Mettu University, Mettu, Ethiopia. ARTICLE INFO ABSTRACT Article history Bacteriocins are antimicrobial peptides or proteins produced by strains of diverse bacterial Received 20/01/2017 species. The antimicrobial activity of this group of natural substances against food borne Available online pathogenic, as well as spoilage bacteria has raised considerable interest for their application in 20/02/2017 food preservation. Depending on the raw materials, processing conditions, distribution, and consumption, the different types of foods offer a great variety of scenarios where food Keywords poisoning, pathogenic, or spoilage bacteria may proliferate. Application of bacteriocins may Proteinaceous, help reduce the use of chemical preservatives and/or the intensity of heat and other physical Bacteriocin, treatments, satisfying the demands of consumers for foods that are fresh tasting, ready to eat, pH Tolerance. and lightly preserved. In recent years, considerable effort has been made to develop food applications for many different bacteriocins and bacteriocinogenic strains. Antibacterial metabolites of lactic acid bacteria have potential as natural preservatives to control the growth of spoilage and pathogenic bacteria in food. Among them, bacteriocin is used as a preservative in food due to its heat stability, wider pH tolerance and its proteolytic activity. Due to thermo stability and pH tolerance. it can withstand heat and acidity/alkanity of food during storage condition. Bacteriocin are ribosomally synthesized peptides originally defined as proteinaceous compound affecting growth or viability of closely related organisms.
    [Show full text]
  • Marmoset Models Commonly Used in Biomedical Research
    Comparative Medicine Vol 53, No 4 Copyright 2003 August 2003 by the American Association for Laboratory Animal Science Pages 383-392 Overview Marmoset Models Commonly Used in Biomedical Research Keith Mansfield, DVM The common marmoset (Callithrix jacchus ) is a small, nonendangered New World primate that is native to Brazil and has been used extensively in biomedical research. Historically the common marmoset has been used in neuro- science, reproductive biology, infectious disease, and behavioral research. Recently, the species has been used in- creasingly in drug development and safety assessment. Advantages relate to size, cost, husbandry, and biosafety issues as well as unique physiologic differences that may be used in model development. Availability and ease of breeding in captivity suggest that they may represent an alternative species to more traditional nonhuman pri- mates. The marmoset models commonly used in biomedical research are presented, with emphasis on those that may provide an alternative to traditional nonhuman primate species. In contrast to many other laboratory animal species, use of nonhuman primate species. nonhuman primates has increased in recent years and there Common marmosets represent an attractive alternative non- currently exists a substantial shortage of such animals for use human primate species for a variety of reasons. These small in biomedical research. The national supply of macaque mon- hardy animals breed well in captivity, with reproductive effi- keys has been unable to meet the current or projected demands ciency that may exceed 150% (number of live born per year/ of the research community. Although efforts are underway to number of breeding females). Furthermore, sexual maturity is increase domestic production and to identify alternative foreign reached by 18 months of age, allowing rapid expansion of exist- sources, this will unlikely alter short-term availability.
    [Show full text]
  • Genomic Analyses of Pneumococci Reveal a Wide Diversity of Bacteriocins
    Bogaardt et al. BMC Genomics (2015) 16:554 DOI 10.1186/s12864-015-1729-4 RESEARCHARTICLE Open Access Genomic analyses of pneumococci reveal a wide diversity of bacteriocins – including pneumocyclicin, a novel circular bacteriocin Carlijn Bogaardt, Andries J van Tonder and Angela B Brueggemann* Abstract Background: One of the most important global pathogens infecting all age groups is Streptococcus pneumoniae (the ‘pneumococcus’). Pneumococci reside in the paediatric nasopharynx, where they compete for space and resources, and one competition strategy is to produce a bacteriocin (antimicrobial peptide or protein) to attack other bacteria and an immunity protein to protect against self-destruction. We analysed a collection of 336 diverse pneumococcal genomes dating from 1916 onwards, identified bacteriocin cassettes, detailed their genetic composition and sequence diversity, and evaluated the data in the context of the pneumococcal population structure. Results: We found that all genomes maintained a blp bacteriocin cassette and we identified several novel blp cassettes and genes. The composition of the ‘bacteriocin/immunity region’ of the blp cassette was highly variable: one cassette possessed six bacteriocin genes and eight putative immunity genes, whereas another cassette had only one of each. Both widely-distributed and highly clonal blp cassettes were identified. Most surprisingly, one-third of pneumococcal genomes also possessed a cassette encoding a novel circular bacteriocin that we called pneumocyclicin, which shared a similar genetic organisation to well-characterised circular bacteriocin cassettes in other bacterial species. Pneumocyclicin cassettes were mainly of one genetic cluster and largely found among seven major pneumococcal clonal complexes. Conclusions: These detailed genomic analyses revealed a novel pneumocyclicin cassette and a wide variety of blp bacteriocin cassettes, suggesting that competition in the nasopharynx is a complex biological phenomenon.
    [Show full text]