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Ravikumaran KS, Armiento S, De Castro C, Molinaro A, Wilson JC, Grice ID, Peak IR. Characterisation of a capsular polysaccharide from Moraxella nonliquefaciens CCUG 348T. Carbohydr Res 2024; 538:109095. [PMID: 38507941 DOI: 10.1016/j.carres.2024.109095] [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: 12/15/2023] [Revised: 02/22/2024] [Accepted: 03/14/2024] [Indexed: 03/22/2024]
Abstract
Moraxella nonliquefaciens is a commensal of the human upper respiratory tract (URT) but on rare occasions is recovered in cases of ocular, septic and pulmonary infections. Hence there is interest in the pathogenic determinants of M. nonliquefaciens, of which outer membrane (OM) structures such as fimbriae and two capsular polysaccharide (CPS) structures, →3)-β-D-GalpNAc-(1→5)-β-Kdop-(2→ and →8)-α-NeuAc-(2→, have been reported in the literature. To further characterise its surface virulence factors, we isolated a novel CPS from M. nonliquefaciens type strain CCUG 348T. This structure was elucidated using NMR data obtained from CPS samples that were subjected to various degrees of mild acid hydrolysis. Together with GLC-MS data, the structure was resolved as a linear polymer composed of two GalfNAc residues consecutively added to Kdo, →3)-β-D-GalfNAc-(1→3)-α-D-GalfNAc-(1→5)-α-(8-OAc)Kdop-(2→. Supporting evidence for this material being CPS was drawn from the proposed CPS biosynthetic locus which encoded a potential GalfNAc transferase, a UDP-GalpNAc mutase for UDP-GalfNAc production and a putative CPS polymerase with predicted GalfNAc and Kdo transferase domains. This study describes a unique CPS composition reported in Moraxella spp. and offers genetic insights into the synthesis and expression of GalfNAc residues, which are rare in bacterial OM glycans.
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Affiliation(s)
- Kosala S Ravikumaran
- School of Pharmacy and Medical Science, Griffith University, Gold Coast Campus, Queensland, 4222, Australia
| | - Samantha Armiento
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Napoli, Italy
| | - Cristina De Castro
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Napoli, Italy
| | - Antonio Molinaro
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126, Napoli, Italy
| | - Jennifer C Wilson
- School of Pharmacy and Medical Science, Griffith University, Gold Coast Campus, Queensland, 4222, Australia
| | - I Darren Grice
- School of Pharmacy and Medical Science, Griffith University, Gold Coast Campus, Queensland, 4222, Australia; Institute for Glycomics, Griffith University, Gold Coast Campus, Queensland, 4222, Australia.
| | - Ian R Peak
- School of Pharmacy and Medical Science, Griffith University, Gold Coast Campus, Queensland, 4222, Australia; Institute for Glycomics, Griffith University, Gold Coast Campus, Queensland, 4222, Australia.
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Woyda R, Oladeinde A, Endale D, Strickland T, Plumblee Lawrence J, Abdo Z. Virulence factors and antimicrobial resistance profiles of Campylobacter isolates recovered from consecutively reused broiler litter. Microbiol Spectr 2023; 11:e0323623. [PMID: 37882583 PMCID: PMC10871742 DOI: 10.1128/spectrum.03236-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 09/19/2023] [Indexed: 10/27/2023] Open
Abstract
IMPORTANCE Campylobacter is a leading cause of foodborne illness in the United States due to consumption of contaminated or mishandled food products, often associated with chicken meat. Campylobacter is common in the microbiota of avian and mammalian gut; however, acquisition of antimicrobial resistance genes (ARGs) and virulence factors (VFs) may result in strains that pose significant threat to public health. Although there are studies investigating the genetic diversity of Campylobacter strains isolated from post-harvest chicken samples, there are limited data on the genome characteristics of isolates recovered from preharvest broiler production. Here, we show that Campylobacter jejuni and Campylobacter coli differ in their carriage of antimicrobial resistance and virulence factors may also differ in their ability to persist in litter during consecutive grow-out of broiler flocks. We found that presence/absence of virulence factors needed for evasion of host defense mechanisms and gut colonization played an integral role in differentiating Campylobacter strains.
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Affiliation(s)
- Reed Woyda
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
- Program of Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
| | | | - Dinku Endale
- Southeast Watershed Research Laboratory, USDA, Tifton, Georgia, USA
| | | | | | - Zaid Abdo
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
- Program of Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
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3
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Li T, Huang J, Yang S, Chen J, Yao Z, Zhong M, Zhong X, Ye X. Pan-Genome-Wide Association Study of Serotype 19A Pneumococci Identifies Disease-Associated Genes. Microbiol Spectr 2023; 11:e0407322. [PMID: 37358412 PMCID: PMC10433855 DOI: 10.1128/spectrum.04073-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 06/04/2023] [Indexed: 06/27/2023] Open
Abstract
Despite the widespread implementation of pneumococcal vaccines, hypervirulent Streptococcus pneumoniae serotype 19A is endemic worldwide. It is still unclear whether specific genetic elements contribute to complex pathogenicity of serotype 19A isolates. We performed a large-scale pan-genome-wide association study (pan-GWAS) of 1,292 serotype 19A isolates sampled from patients with invasive disease and asymptomatic carriers. To address the underlying disease-associated genotypes, a comprehensive analysis using three methods (Scoary, a linear mixed model, and random forest) was performed to compare disease and carriage isolates to identify genes consistently associated with disease phenotype. By using three pan-GWAS methods, we found consensus on statistically significant associations between genotypes and disease phenotypes (disease or carriage), with a subset of 30 consistently significant disease-associated genes. The results of functional annotation revealed that these disease-associated genes had diverse predicted functions, including those that participated in mobile genetic elements, antibiotic resistance, virulence, and cellular metabolism. Our findings suggest the multifactorial pathogenicity nature of this hypervirulent serotype and provide important evidence for the design of novel protein-based vaccines to prevent and control pneumococcal disease. IMPORTANCE It is important to understand the genetic and pathogenic characteristics of S. pneumoniae serotype 19A, which may provide important information for the prevention and treatment of pneumococcal disease. This global large-sample pan-GWAS study has identified a subset of 30 consistently significant disease-associated genes that are involved in mobile genetic elements, antibiotic resistance, virulence, and cellular metabolism. These findings suggest the multifactorial pathogenicity nature of hypervirulent S. pneumoniae serotype 19A isolates and provide implications for the design of novel protein-based vaccines.
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Affiliation(s)
- Ting Li
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jiayin Huang
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shimin Yang
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
| | - Jianyu Chen
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
| | - Zhenjiang Yao
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
| | - Minghao Zhong
- Department of Prevention and Health Care, The Sixth People’s Hospital of Dongguan City, Guangdong, China
| | - Xinguang Zhong
- Department of Prevention and Health Care, The Sixth People’s Hospital of Dongguan City, Guangdong, China
| | - Xiaohua Ye
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China
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4
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Woyda R, Oladeinde A, Endale D, Strickland T, Lawrence JP, Abdo Z. Broiler house environment and litter management practices impose selective pressures on antimicrobial resistance genes and virulence factors of Campylobacter. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.02.526821. [PMID: 36778422 PMCID: PMC9915665 DOI: 10.1101/2023.02.02.526821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Campylobacter infections are a leading cause of bacterial diarrhea in humans globally. Infections are due to consumption of contaminated food products and are highly associated with chicken meat, with chickens being an important reservoir for Campylobacter. Here, we characterized the genetic diversity of Campylobacter species detected in broiler chicken litter over three consecutive flocks and determined their antimicrobial resistance and virulence factor profiles. Antimicrobial susceptibility testing and whole genome sequencing were performed on Campylobacter jejuni (n = 39) and Campylobacter coli (n = 5) isolates. All C. jejuni isolates were susceptible to all antibiotics tested while C. coli (n =4) were resistant to only tetracycline and harbored the tetracycline-resistant ribosomal protection protein (TetO). Virulence factors differed within and across grow houses but were explained by the isolates' flock cohort, species and multilocus sequence type. Virulence factors involved in the ability to invade and colonize host tissues and evade host defenses were absent from flock cohort 3 C. jejuni isolates as compared to flock 1 and 2 isolates. Our results show that virulence factors and antimicrobial resistance genes differed by the isolates' multilocus sequence type and by the flock cohort they were present in. These data suggest that the house environment and litter management practices performed imposed selective pressures on antimicrobial resistance genes and virulence factors. In particular, the absence of key virulence factors within the final flock cohort 3 isolates suggests litter reuse selected for Campylobacter strains that are less likely to colonize the chicken host.
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Affiliation(s)
- Reed Woyda
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
- Program of Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
| | | | - Dinku Endale
- Southeast Watershed Research Laboratory, USDA, Tifton, GA, 31793
| | | | | | - Zaid Abdo
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, USA
- Program of Cell and Molecular Biology, Colorado State University, Fort Collins, Colorado, USA
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5
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Chi C, Xu R, Chen Q, Zhang X, Shi X, Jin H, Yin F, Jia H, Zhang L, Yang D, Ju J, Li Q, Ma M. Structural Insight into a Metal-Dependent Mutase Revealing an Arginine Residue-Covalently Mediated Interconversion between Nucleotide-Based Pyranose and Furanose. ACS Catal 2023. [DOI: 10.1021/acscatal.2c04907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Changbiao Chi
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Run Xu
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
| | - Qianqian Chen
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Xiaohui Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Xiaomeng Shi
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Hongwei Jin
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Fuling Yin
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Hongli Jia
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Liangren Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Donghui Yang
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Jianhua Ju
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
| | - Qinglian Li
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China
| | - Ming Ma
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
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Riegert AS, Narindoshvili T, Platzer NE, Raushel FM. Functional Characterization of a HAD Phosphatase Involved in Capsular Polysaccharide Biosynthesis in Campylobacter jejuni. Biochemistry 2022; 61:2431-2440. [PMID: 36214481 PMCID: PMC9633586 DOI: 10.1021/acs.biochem.2c00484] [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] [Indexed: 11/28/2022]
Abstract
Campylobacter jejuni is a Gram-negative, pathogenic bacterium found in the intestinal tracts of chickens and many other farm animals. C. jejuni infection results in campylobacteriosis, which can cause nausea, diarrhea, fever, cramps, and death. The surface of the bacterium is coated with a thick layer of sugar known as the capsular polysaccharide. This highly modified polysaccharide contains an unusual d-glucuronamide moiety in serotypes HS:2 and HS:19. Previously, we have demonstrated that a phosphorylated glucuronamide intermediate is synthesized in C. jejuni NCTC 11168 (serotype HS:2) by cumulative reactions of three enzymes: Cj1441, Cj1436/Cj1437, and Cj1438. Cj1441 functions as a UDP-d-glucose dehydrogenase to make UDP-d-glucuronate; then Cj1436 or Cj1437 catalyzes the formation of ethanolamine phosphate or S-serinol phosphate, respectively, and finally Cj1438 catalyzes amide bond formation using d-glucuronate and either ethanolamine phosphate or S-serinol phosphate. Here, we investigated the final d-glucuronamide-modifying enzyme, Cj1435. Cj1435 was shown to catalyze the hydrolysis of the phosphate esters from either the d-glucuronamide of ethanolamine phosphate or S-serinol phosphate. Kinetic constants for a range of substrates were determined, and the stereoselectivity of the enzyme for the hydrolysis of glucuronamide of S-serinol phosphate was established using 31P nuclear magnetic resonance spectroscopy. A bioinformatic analysis of Cj1435 reveals it to be a member of the HAD phosphatase superfamily with a unique DXXE catalytic motif.
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Affiliation(s)
- Alexander S. Riegert
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX 77843, United States
| | - Tamari Narindoshvili
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, United States
| | - Nicole E. Platzer
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, United States
| | - Frank M. Raushel
- Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX 77843, United States
- Department of Chemistry, Texas A&M University, College Station, TX, 77843, United States
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7
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Chen WJ, Han SB, Xie ZB, Huang HS, Jiang DH, Gong SS, Sun Q. Efficient Synthesis of UDP-Furanoses via 4,5-Dicyanoimidazole(DCI)-Promoted Coupling of Furanosyl-1-Phosphates with Uridine Phosphoropiperidate. Molecules 2019; 24:molecules24040655. [PMID: 30781738 PMCID: PMC6412210 DOI: 10.3390/molecules24040655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/10/2019] [Accepted: 02/11/2019] [Indexed: 11/16/2022] Open
Abstract
A P(V)-N activation method based on nucleoside phosphoropiperidate/DCI system has been developed for improved synthesis of diverse UDP-furanoses. The reaction conditions including temperature, amount of activator, and reaction time were optimized to alleviate the degradation of UDP-furanoses to cyclic phosphates. In addition, an efficient and facile phosphoramidite route was employed for the preparation of furanosyl-1-phosphates.
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Affiliation(s)
- Wei-Jie Chen
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
| | - Shuai-Bo Han
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
| | - Zhen-Biao Xie
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
| | - Hua-Shan Huang
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
| | - Duo-Hua Jiang
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
| | - Shan-Shan Gong
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
| | - Qi Sun
- Jiangxi Key Laboratory of Organic Chemistry, Jiangxi Science and Technology Normal University, 605 Fenglin Avenue, Nanchang 330013, China.
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8
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Deciphering the sugar biosynthetic pathway and tailoring steps of nucleoside antibiotic A201A unveils a GDP-l-galactose mutase. Proc Natl Acad Sci U S A 2017; 114:4948-4953. [PMID: 28438999 DOI: 10.1073/pnas.1620191114] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Galactose, a monosaccharide capable of assuming two possible configurational isomers (d-/l-), can exist as a six-membered ring, galactopyranose (Galp), or as a five-membered ring, galactofuranose (Galf). UDP-galactopyranose mutase (UGM) mediates the conversion of pyranose to furanose thereby providing a precursor for d-Galf Moreover, UGM is critical to the virulence of numerous eukaryotic and prokaryotic human pathogens and thus represents an excellent antimicrobial drug target. However, the biosynthetic mechanism and relevant enzymes that drive l-Galf production have not yet been characterized. Herein we report that efforts to decipher the sugar biosynthetic pathway and tailoring steps en route to nucleoside antibiotic A201A led to the discovery of a GDP-l-galactose mutase, MtdL. Systematic inactivation of 18 of the 33 biosynthetic genes in the A201A cluster and elucidation of 10 congeners, coupled with feeding and in vitro biochemical experiments, enabled us to: (i) decipher the unique enzyme, GDP-l-galactose mutase associated with production of two unique d-mannose-derived sugars, and (ii) assign two glycosyltransferases, four methyltransferases, and one desaturase that regiospecifically tailor the A201A scaffold and display relaxed substrate specificities. Taken together, these data provide important insight into the origin of l-Galf-containing natural product biosynthetic pathways with likely ramifications in other organisms and possible antimicrobial drug targeting strategies.
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9
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Sharma S, Erickson KM, Troutman JM. Complete Tetrasaccharide Repeat Unit Biosynthesis of the Immunomodulatory Bacteroides fragilis Capsular Polysaccharide A. ACS Chem Biol 2017; 12:92-101. [PMID: 28103676 DOI: 10.1021/acschembio.6b00931] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Capsular polysaccharide A (CPSA) is a four-sugar repeating unit polymer found on the surface of the gut symbiont Bacteroides fragilis that has therapeutic potential in animal models of autoimmune disorders. This therapeutic potential has been credited to its zwitterionic character derived from a positively charged N-acetyl-4-aminogalactosamine (AADGal) and a negatively charged 4,6-O-pyruvylated galactose (PyrGal). In this report, using a fluorescent polyisoprenoid chemical probe, the complete enzymatic assembly of the CPSA tetrasaccharide repeat unit is achieved. The proposed pyruvyltransferase, WcfO; galactopyranose mutase, WcfM; and glycosyltransferases, WcfP and WcfN, encoded by the CPSA biosynthesis gene cluster were heterologously expressed and functionally characterized. Pyruvate modification, catalyzed by WcfO, was found to occur on galactose of the polyisoprenoid-linked disaccharide (AADGal-Gal), and did not occur on galactose linked to uridine diphosphate (UDP) or a set of nitrophenyl-galactose analogues. This pyruvate modification was also found to be required for the incorporation of the next sugar in the pathway N-acetylgalactosamine (GalNAc) by the glycosyltransferase WcfP. The pyruvate acetal modification of a galactose has not been previously explored in the context of a polysaccharide biosynthesis pathway, and this work demonstrates the importance of this modification to repeat unit assembly. Upon production of the polyisoprenoid-linked AADGal-PyrGal-GalNAc, the proteins WcfM and WcfN were found to work in concert to form the final tetrasaccharide, where WcfM formed UDP-galactofuranose (Galf) and WcfN transfers Galf to the AADGal-PyrGal-GalNAc. This work demonstrates the first enzymatic assembly of the tetrasaccharide repeat unit of CPSA in a sequential single pot reaction.
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Affiliation(s)
- Sunita Sharma
- Department
of Chemistry, ‡The Center for Biomedical Engineering and Science, §Department of Biological Sciences, ∥Nanoscale Science
Program, University of North Carolina at Charlotte, 9201 University
City Blvd., Charlotte, North
Carolina 28223, United States
| | - Katelyn M. Erickson
- Department
of Chemistry, ‡The Center for Biomedical Engineering and Science, §Department of Biological Sciences, ∥Nanoscale Science
Program, University of North Carolina at Charlotte, 9201 University
City Blvd., Charlotte, North
Carolina 28223, United States
| | - Jerry M. Troutman
- Department
of Chemistry, ‡The Center for Biomedical Engineering and Science, §Department of Biological Sciences, ∥Nanoscale Science
Program, University of North Carolina at Charlotte, 9201 University
City Blvd., Charlotte, North
Carolina 28223, United States
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Chalcone Isomerase from Eubacterium ramulus Catalyzes the Ring Contraction of Flavanonols. J Bacteriol 2016; 198:2965-2974. [PMID: 27551015 DOI: 10.1128/jb.00490-16] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 08/05/2016] [Indexed: 01/07/2023] Open
Abstract
The enzyme catalyzing the ring-contracting conversion of the flavanonol taxifolin to the auronol alphitonin in the course of flavonoid degradation by the human intestinal anaerobe Eubacterium ramulus was purified and characterized. It stereospecifically catalyzed the isomerization of (+)-taxifolin but not that of (-)-taxifolin. The Km for (+)-taxifolin was 6.4 ± 0.8 μM, and the Vmax was 108 ± 4 μmol min-1 (mg protein)-1 The enzyme also isomerized (+)-dihydrokaempferol, another flavanonol, to maesopsin. Inspection of the encoding gene revealed its complete identity to that of the gene encoding chalcone isomerase (CHI) from E. ramulus Based on the reported X-ray crystal structure of CHI (M. Gall et al., Angew Chem Int Ed 53:1439-1442, 2014, http://dx.doi.org/10.1002/anie.201306952), docking experiments suggest the substrate binding mode of flavanonols and their stereospecific conversion. Mutation of the active-site histidine (His33) to alanine led to a complete loss of flavanonol isomerization by CHI, which indicates that His33 is also essential for this activity. His33 is proposed to mediate the stereospecific abstraction of a proton from the hydroxymethylene carbon of the flavanonol C-ring followed by ring opening and recyclization. A flavanonol-isomerizing enzyme was also identified in the flavonoid-converting bacterium Flavonifractor plautii based on its 50% sequence identity to the CHI from E. ramulus IMPORTANCE: Chalcone isomerase was known to be involved in flavone/flavanone conversion by the human intestinal bacterium E. ramulus Here we demonstrate that this enzyme moreover catalyzes a key step in the breakdown of flavonols/flavanonols. Thus, a single isomerase plays a dual role in the bacterial conversion of dietary bioactive flavonoids. The identification of a corresponding enzyme in the human intestinal bacterium F. plautii suggests a more widespread occurrence of this isomerase in flavonoid-degrading bacteria.
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Ashmus RA, Jayasuriya AB, Lim YJ, O’Doherty GA, Lowary TL. De Novo Asymmetric Synthesis of a 6-O-Methyl-d-glycero-l-gluco-heptopyranose-Derived Thioglycoside for the Preparation of Campylobacter jejuni NCTC11168 Capsular Polysaccharide Fragments. J Org Chem 2016; 81:3058-63. [DOI: 10.1021/acs.joc.6b00296] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Roger A. Ashmus
- Alberta
Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Anushka B. Jayasuriya
- Alberta
Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Ying-Jie Lim
- Alberta
Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - George A. O’Doherty
- Department
of Chemistry, Northeastern University, 360 Huntington Ave., Boston, Massachusetts 02115, United States
| | - Todd L. Lowary
- Alberta
Glycomics Centre and Department of Chemistry, The University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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12
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Vinnitskiy DZ, Ustyuzhanina NE, Nifantiev NE. Natural bacterial and plant biomolecules bearing α-d-glucuronic acid residues. Russ Chem Bull 2016. [DOI: 10.1007/s11172-015-1010-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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13
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Schieck E, Lartigue C, Frey J, Vozza N, Hegermann J, Miller RA, Valguarnera E, Muriuki C, Meens J, Nene V, Naessens J, Weber J, Lowary TL, Vashee S, Feldman MF, Jores J. Galactofuranose in Mycoplasma mycoides is important for membrane integrity and conceals adhesins but does not contribute to serum resistance. Mol Microbiol 2015; 99:55-70. [PMID: 26354009 DOI: 10.1111/mmi.13213] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2015] [Indexed: 12/20/2022]
Abstract
Mycoplasma mycoides subsp. capri (Mmc) and subsp. mycoides (Mmm) are important ruminant pathogens worldwide causing diseases such as pleuropneumonia, mastitis and septicaemia. They express galactofuranose residues on their surface, but their role in pathogenesis has not yet been determined. The M. mycoides genomes contain up to several copies of the glf gene, which encodes an enzyme catalysing the last step in the synthesis of galactofuranose. We generated a deletion of the glf gene in a strain of Mmc using genome transplantation and tandem repeat endonuclease coupled cleavage (TREC) with yeast as an intermediary host for the genome editing. As expected, the resulting YCp1.1-Δglf strain did not produce the galactofuranose-containing glycans as shown by immunoblots and immuno-electronmicroscopy employing a galactofuranose specific monoclonal antibody. The mutant lacking galactofuranose exhibited a decreased growth rate and a significantly enhanced adhesion to small ruminant cells. The mutant was also 'leaking' as revealed by a β-galactosidase-based assay employing a membrane impermeable substrate. These findings indicate that galactofuranose-containing polysaccharides conceal adhesins and are important for membrane integrity. Unexpectedly, the mutant strain showed increased serum resistance.
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Affiliation(s)
- Elise Schieck
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, 00100, Nairobi, Kenya
| | - Carole Lartigue
- UMR 1332 Biologie du Fruit et Pathologie, The French National Institute for Agricultural Research, INRA-Université Bordeaux, Segalen, 71, avenue Edouard Bourlaux, CS20032, F-33882, Villenave D'Ornon CEDEX, Bordeaux, France.,UMR 1332 de Biologie du Fruit et Pathologie, Université Bordeaux, F-33140, Villenave d'Ornon, Bordeaux, France
| | - Joachim Frey
- Institute of Veterinary Bacteriology, University of Bern, CH-3001, Bern, Switzerland
| | - Nicolas Vozza
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada
| | - Jan Hegermann
- Institute of Functional and Applied Anatomy, Hannover Medical School, Hannover, Germany.,Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Member of the German Center for Lung Research (DZL), Hannover, Germany.,REBIRTH Cluster of Excellence, Hannover, Germany
| | - Rachel A Miller
- Department of Food Science, Cornell University, Ithaca, NY, USA
| | - Ezequiel Valguarnera
- Department of Molecular Microbiology, Washington University School of Medicine St Louis, 660 South Euclid Avenue, St Louis, MO 63110, USA
| | - Cecilia Muriuki
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, 00100, Nairobi, Kenya
| | - Jochen Meens
- Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Vish Nene
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, 00100, Nairobi, Kenya
| | - Jan Naessens
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, 00100, Nairobi, Kenya
| | - Johann Weber
- Center for Integrative Genomics, Lausanne Genomic Technologies Facility,University of Lausanne, Lausanne, Switzerland
| | - Todd L Lowary
- Department of Chemistry, Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada
| | - Sanjay Vashee
- J. Craig Venter Institute, 9704 Medical Center Drive, MD 20850, Rockville, USA
| | - Mario F Feldman
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada.,Department of Molecular Microbiology, Washington University School of Medicine St Louis, 660 South Euclid Avenue, St Louis, MO 63110, USA
| | - Joerg Jores
- International Livestock Research Institute, Old Naivasha Road, P.O. Box 30709, 00100, Nairobi, Kenya.,Institute of Veterinary Bacteriology, University of Bern, CH-3001, Bern, Switzerland
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14
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Eppe G, El Bkassiny S, Vincent SP. Galactofuranose Biosynthesis: Discovery, Mechanisms and Therapeutic Relevance. CARBOHYDRATES IN DRUG DESIGN AND DISCOVERY 2015. [DOI: 10.1039/9781849739993-00209] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Galactofuranose, the atypical and thermodynamically disfavored form of d-galactose, has in reality a very old history in chemistry and biochemistry. The purpose of this book chapter is to give an overview on the fundamental aspects of the galactofuranose biosynthesis, from the biological occurrence to the search of inhibitors.
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Affiliation(s)
- Guillaume Eppe
- University of Namur, Département de Chimie, Laboratoire de Chimie Bio-Organique rue de Bruxelles 61 B-5000 Namur Belgium
| | - Sandy El Bkassiny
- University of Namur, Département de Chimie, Laboratoire de Chimie Bio-Organique rue de Bruxelles 61 B-5000 Namur Belgium
| | - Stéphane P. Vincent
- University of Namur, Département de Chimie, Laboratoire de Chimie Bio-Organique rue de Bruxelles 61 B-5000 Namur Belgium
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15
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Kuppala R, Borrelli S, Slowski K, Sanders DAR, Ravindranathan Kartha KP, Pinto BM. Synthesis and biological evaluation of nonionic substrate mimics of UDP-Galp as candidate inhibitors of UDP galactopyranose mutase (UGM). Bioorg Med Chem Lett 2015; 25:1995-7. [PMID: 25819094 DOI: 10.1016/j.bmcl.2015.03.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 02/28/2015] [Accepted: 03/03/2015] [Indexed: 11/30/2022]
Abstract
The synthesis of 1-[5-O-(α-D-galactopyranosyl)-D-glucityl]pyrimidine-2,4(3H)-dione and 1-[(5-O-(β-D-galactopyranosyl)-D-glucityl]pyrimidine-2,4(3H)-dione as non-ionic substrate mimics of UDP-Galp are described. UDP-Galp is a precursor of Galf, which is a primary component of the cell-wall glycans of several microorganisms. The interconversion of UDP-Galp and UDP-Galf is catalyzed by UDP galactopyranose mutase (UGM); its inhibition comprises a mode of compromising the microorganisms. The nonionic polyhydroxylated chain was intended to mimic the ionic pyrophosphate group and the ribose moiety in UDP-Galp and increase the bioavailabilities of the candidate inhibitors. Inhibition assays with UGM of Mycobacterium tuberculosis showed only weak inhibition of the enzyme by these compounds.
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Affiliation(s)
- Ramakrishna Kuppala
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada; Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab 160062, India
| | - Silvia Borrelli
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | - Kathryn Slowski
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N 5C9, Canada
| | - David A R Sanders
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan S7N 5C9, Canada
| | - K P Ravindranathan Kartha
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), S.A.S. Nagar, Punjab 160062, India
| | - B Mario Pinto
- Department of Chemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada.
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16
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Comparative genome analysis of Campylobacter fetus subspecies revealed horizontally acquired genetic elements important for virulence and niche specificity. PLoS One 2014; 9:e85491. [PMID: 24416416 PMCID: PMC3887049 DOI: 10.1371/journal.pone.0085491] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 11/28/2013] [Indexed: 01/03/2023] Open
Abstract
Campylobacter fetus are important animal and human pathogens and the two major subspecies differ strikingly in pathogenicity. C. fetus subsp. venerealis is highly niche-adapted, mainly infecting the genital tract of cattle. C. fetus subsp. fetus has a wider host-range, colonizing the genital- and intestinal-tract of animals and humans. We report the complete genomic sequence of C. fetus subsp. venerealis 84-112 and comparisons to the genome of C. fetus subsp. fetus 82-40. Functional analysis of genes predicted to be involved in C. fetus virulence was performed. The two subspecies are highly syntenic with 92% sequence identity but C. fetus subsp. venerealis has a larger genome and an extra-chromosomal element. Aside from apparent gene transfer agents and hypothetical proteins, the unique genes in both subspecies comprise two known functional groups: lipopolysaccharide production, and type IV secretion machineries. Analyses of lipopolysaccharide-biosynthesis genes in C. fetus isolates showed linkage to particular pathotypes, and mutational inactivation demonstrated their roles in regulating virulence and host range. The comparative analysis presented here broadens knowledge of the genomic basis of C. fetus pathogenesis and host specificity. It further highlights the importance of surface-exposed structures to C. fetus pathogenicity and demonstrates how evolutionary forces optimize the fitness and host-adaptation of these pathogens.
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17
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Snitynsky RB, Lowary TL. Synthesis of nitrogen-containing furanose sugar nucleotides for use as enzymatic probes. Org Lett 2013; 16:212-5. [PMID: 24328953 DOI: 10.1021/ol4032073] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The sugar nucleotides UDP-2-acetamido-2-deoxy-α-D-galactofuranose (UDP-GalfNAc) and UDP-2-azido-2-deoxy-α-D-galactofuranose (UDP-GalfN3) have been synthesized in preparative scale for the first time. These compounds are useful probes for studying the biosynthesis of glycans containing galactofuranose and/or 2-acetamido-2-deoxy-α-D-galactofuranose residues.
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Affiliation(s)
- Ryan B Snitynsky
- Alberta Glycomics Centre and Department of Chemistry, Gunning-Lemieux Chemistry Centre, University of Alberta , Edmonton, Alberta, Canada T6G 2G2
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18
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N'Go I, Golten S, Ardá A, Cañada J, Jiménez-Barbero J, Linclau B, Vincent SP. Tetrafluorination of sugars as strategy for enhancing protein-carbohydrate affinity: application to UDP-Galp mutase inhibition. Chemistry 2013; 20:106-12. [PMID: 24311368 DOI: 10.1002/chem.201303693] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Indexed: 01/16/2023]
Abstract
Tetrafluorinated analogues of both UDP-galactopyranose and UDP-galactofuranose have been synthesized and assayed against UDP-galactopyranose mutase, a key enzyme for Mycobacterium tuberculosis cell wall biosynthesis. Competition assays and STD-NMR spectroscopy techniques have evidenced not only the first unambiguous case of affinity enhancement through local sugar polyfluorination, but also showed that tetrafluorination can still have a beneficial effect on binding when monofluorination at the same position does not.
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Affiliation(s)
- Inès N'Go
- Department of Chemistry, University of Namur, Rue de Bruxelles 61, 5000 Namur (Belgium)
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19
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Poulin MB, Shi Y, Protsko C, Dalrymple SA, Sanders DAR, Pinto BM, Lowary TL. Specificity of a UDP-GalNAc pyranose-furanose mutase: a potential therapeutic target for Campylobacter jejuni infections. Chembiochem 2013; 15:47-56. [PMID: 24302429 DOI: 10.1002/cbic.201300653] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Indexed: 12/23/2022]
Abstract
Pyranose-furanose mutases are essential enzymes in the life cycle of a number of microorganisms, but are absent in mammalian systems, and hence represent novel targets for drug development. To date, all such mutases show preferential recognition of a single substrate (e.g., UDP-Gal). We report here the detailed structural characterization of the first bifunctional pyranose-furanose mutase, which recognizes both UDP-Gal and UDP-GalNAc. The enzyme under investigation (cjUNGM) is involved in the biosynthesis of capsular polysaccharides (CPSs) in Campylobacter jejuni 11168. These CPSs are known virulence factors that are required for adhesion and invasion of human epithelial cells. Using a combination of UV/visible spectroscopy, X-ray crystallography, saturation transfer difference NMR spectroscopy, molecular dynamics and CORCEMA-ST calculations, we have characterized the binding of the enzyme to both UDP-Galp and UDP-GalpNAc, and compared these interactions with those of a homologous monofunctional mutase enzyme from E. coli (ecUGM). These studies reveal that two arginines in cjUNGM, Arg59 and Arg168, play critical roles in the catalytic mechanism of the enzyme and in controlling its specificity to ultimately lead to a GalfNAc-containing CPS. In ecUGM, these arginines are replaced with histidine and lysine, respectively, and this results in an enzyme that is selective for UDP-Gal. We propose that these changes in amino acids allow C. jejuni 11168 to produce suitable quantities of the sugar nucleotide substrate required for the assembly of a CPS containing GalfNAc, which is essential for viability.
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Affiliation(s)
- Myles B Poulin
- Alberta Glycomics Centre and Department of Chemistry, The University of Alberta, Gunning-Lemieux Chemistry Centre, 11227 Saskatchewan Drive, Edmonton, AB T6G 2G2 (Canada)
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20
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Dalrymple SA, Ko J, Sheoran I, Kaminskyj SGW, Sanders DAR. Elucidation of substrate specificity in Aspergillus nidulans UDP-galactose-4-epimerase. PLoS One 2013; 8:e76803. [PMID: 24116166 PMCID: PMC3792076 DOI: 10.1371/journal.pone.0076803] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 08/27/2013] [Indexed: 11/18/2022] Open
Abstract
The frequency of invasive fungal infections has rapidly increased in recent years. Current clinical treatments are experiencing decreased potency due to severe host toxicity and the emergence of fungal drug resistance. As such, new targets and their corresponding synthetic pathways need to be explored for drug development purposes. In this context, galactofuranose residues, which are employed in fungal cell wall construction, but are notably absent in animals, represent an appealing target. Herein we present the structural and biochemical characterization of UDP-galactose-4-epimerase from Aspergillus nidulans which produces the precursor UDP-galactopyranose required for galactofuranose synthesis. Examination of the structural model revealed both NAD+ and UDP-glucopyranose were bound within the active site cleft in a near identical fashion to that found in the Human epimerase. Mutational studies on the conserved catalytic motif support a similar mechanism to that established for the Human counterpart is likely operational within the A. nidulans epimerase. While the Km and kcat for the enzyme were determined to be 0.11 mM and 12.8 s-1, respectively, a single point mutation, namely L320C, activated the enzyme towards larger N-acetylated substrates. Docking studies designed to probe active site affinity corroborate the experimentally determined activity profiles and support the kinetic inhibition results.
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Affiliation(s)
- Sean A. Dalrymple
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - John Ko
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Inder Sheoran
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | | | - David A. R. Sanders
- Department of Chemistry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- * E-mail:
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21
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Sternberg MJE, Tamaddoni-Nezhad A, Lesk VI, Kay E, Hitchen PG, Cootes A, van Alphen LB, Lamoureux MP, Jarrell HC, Rawlings CJ, Soo EC, Szymanski CM, Dell A, Wren BW, Muggleton SH. Gene function hypotheses for the Campylobacter jejuni glycome generated by a logic-based approach. J Mol Biol 2012; 425:186-97. [PMID: 23103756 PMCID: PMC3546167 DOI: 10.1016/j.jmb.2012.10.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Revised: 10/15/2012] [Accepted: 10/17/2012] [Indexed: 11/26/2022]
Abstract
Increasingly, experimental data on biological systems are obtained from several sources and computational approaches are required to integrate this information and derive models for the function of the system. Here, we demonstrate the power of a logic-based machine learning approach to propose hypotheses for gene function integrating information from two diverse experimental approaches. Specifically, we use inductive logic programming that automatically proposes hypotheses explaining the empirical data with respect to logically encoded background knowledge. We study the capsular polysaccharide biosynthetic pathway of the major human gastrointestinal pathogen Campylobacter jejuni. We consider several key steps in the formation of capsular polysaccharide consisting of 15 genes of which 8 have assigned function, and we explore the extent to which functions can be hypothesised for the remaining 7. Two sources of experimental data provide the information for learning—the results of knockout experiments on the genes involved in capsule formation and the absence/presence of capsule genes in a multitude of strains of different serotypes. The machine learning uses the pathway structure as background knowledge. We propose assignments of specific genes to five previously unassigned reaction steps. For four of these steps, there was an unambiguous optimal assignment of gene to reaction, and to the fifth, there were three candidate genes. Several of these assignments were consistent with additional experimental results. We therefore show that the logic-based methodology provides a robust strategy to integrate results from different experimental approaches and propose hypotheses for the behaviour of a biological system.
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Affiliation(s)
- Michael J E Sternberg
- Centre for Integrative Systems Biology, Imperial College London, London SW7 2AZ, UK.
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22
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Ansiaux C, N'Go I, Vincent SP. Reversible and Efficient Inhibition of UDP-Galactopyranose Mutase by Electrophilic, Constrained and Unsaturated UDP-Galactitol Analogues. Chemistry 2012; 18:14860-6. [DOI: 10.1002/chem.201202302] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Indexed: 11/09/2022]
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23
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Chlubnova I, Legentil L, Dureau R, Pennec A, Almendros M, Daniellou R, Nugier-Chauvin C, Ferrières V. Specific and non-specific enzymes for furanosyl-containing conjugates: biosynthesis, metabolism, and chemo-enzymatic synthesis. Carbohydr Res 2012; 356:44-61. [PMID: 22554502 DOI: 10.1016/j.carres.2012.04.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 04/02/2012] [Accepted: 04/03/2012] [Indexed: 11/27/2022]
Abstract
There is no doubt now that the synthesis of compounds of varying complexity such as saccharides and derivatives thereof continuously grows with enzymatic methods. This review focuses on recent basic knowledge on enzymes specifically involved in the biosynthesis and degradation of furanosyl-containing polysaccharides and conjugates. Moreover, and when possible, biocatalyzed approaches, alternative to standard synthesis, will be detailed in order to strengthen the high potential of these biocatalysts to go further with the preparation of rare furanosides. Interesting results will be also proposed with chemo-enzymatic processes based on nonfuranosyl-specific enzymes.
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Affiliation(s)
- Ilona Chlubnova
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Avenue du Général Leclerc, CS 50837, 35708 Rennes Cedex 7, France
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24
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Dureau R, Legentil L, Daniellou R, Ferrières V. Two-step synthesis of per-O-acetylfuranoses: optimization and rationalization. J Org Chem 2012; 77:1301-7. [PMID: 22283704 DOI: 10.1021/jo201913f] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A simple two-step procedure yielding peracetylated furanoses directly from free aldoses was implemented. Key steps of the method are (i) highly selective formation of per-O-(tert-butyldimethylsilyl)furanoses and (ii) their clean conversion into acetyl ones without isomerization. This approach was easily applied to galactose and structurally related carbohydrates such as arabinose, fucose, methyl galacturonate and N-acetylgalactosamine to give the corresponding peracetylated targets. The success of this procedure relied on the control of at least three parameters: (i) the tautomeric equilibrium of the starting unprotected oses, (ii) the steric hindrance of both targeted furanoses and silylating agent, and finally, (iii) the reactivity of each soft nucleophile during the protecting group interconversion.
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Affiliation(s)
- Rémy Dureau
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Avenue du Général Leclerc, CS 50837, 35708 Rennes Cedex 7, France
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25
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Peng W, Jayasuriya AB, Imamura A, Lowary TL. Synthesis of the 6-O-Methyl-d-glycero-α-l-gluco-heptopyranose Moiety Present in the Capsular Polysaccharide from Campylobacter jejuni NCTC 11168. Org Lett 2011; 13:5290-3. [DOI: 10.1021/ol202152r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wenjie Peng
- Alberta Innovates Centre for Carbohydrate Science and Department of Chemistry, The University of Alberta, Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2 Canada
| | - Anushka B. Jayasuriya
- Alberta Innovates Centre for Carbohydrate Science and Department of Chemistry, The University of Alberta, Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2 Canada
| | - Akihiro Imamura
- Alberta Innovates Centre for Carbohydrate Science and Department of Chemistry, The University of Alberta, Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2 Canada
| | - Todd L. Lowary
- Alberta Innovates Centre for Carbohydrate Science and Department of Chemistry, The University of Alberta, Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2 Canada
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26
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Abstract
Carbohydrates in the thermodynamically disfavored furanose ring conformation are not present in mammalian glycoconjugates, but are widespread in the glycans produced by many bacterial pathogens. In bacteria, these furanose sugars are often found in cell surface glycoconjugates, and are essential for the viability or virulence of the organisms. As a result, the enzymes involved in the biosynthesis of bacterial furanosides are attractive targets as potential selective antimicrobial chemotherapeutics. However, before such chemotherapeutics can be designed, synthesized, and evaluated, more information about the activity and specificity of these enzymes is required. This chapter describes assays that have been used to study enzymes involved in the biosynthesis of one of the most abundant naturally occurring furanose residues, galactofuranose (Galf). In particular, the focus is on UDP-galactopyranose mutase and galactofuranosyltransferases. The assays described in this chapter require UDP-galactofuranose (UDP-Galf); therefore, a procedure for the preparation of UDP-Galf, as well as various UDP-Galf derivatives, using a three-enzyme chemoenzymatic procedure, is also described.
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Affiliation(s)
- Myles B Poulin
- The Alberta Ingenuity Centre for Carbohydrate Science, Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
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