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Thomson NM, Gilroy R, Getino M, Foster-Nyarko E, van Vliet AH, La Ragione RM, Pallen MJ. Remarkable genomic diversity among Escherichia isolates recovered from healthy chickens. PeerJ 2022; 10:e12935. [PMID: 35251780 PMCID: PMC8896058 DOI: 10.7717/peerj.12935] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 01/23/2022] [Indexed: 01/11/2023] Open
Abstract
The genus Escherichia has been extensively studied and it is known to encompass a range of commensal and pathogenic bacteria that primarily inhabit the gastrointestinal tracts of warm-blooded vertebrates. However, the presence of E. coli as a model organism and potential pathogen has diverted attention away from commensal strains and other species in the genus. To investigate the diversity of Escherichia in healthy chickens, we collected fecal samples from antibiotic-free Lohmann Brown layer hens and determined the genome sequences of 100 isolates, 81 of which were indistinguishable at the HC0 level of the Hierarchical Clustering of Core Genome Multi-Locus Sequence Typing scheme. Despite initial selection on CHROMagar Orientation medium, which is considered selective for E. coli, in silico phylotyping and core genome single nucleotide polymorphism analysis revealed the presence of at least one representative of all major clades of Escherichia, except for E. albertii, Shigella, and E. coli phylogroup B2 and cryptic clade I. The most frequent phylogenomic groups were E. coli phylogroups A and B1 and E. ruysiae (clades III and IV). We compiled a collection of reference strains isolated from avian sources (predominantly chicken), representing every Escherichia phylogroup and species, and used it to confirm the phylogeny and diversity of our isolates. Overall, the isolates carried low numbers of the virulence and antibiotic resistance genes typically seen in avian pathogenic E. coli. Notably, the clades not recovered are ones that have been most strongly associated with virulence by other studies.
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Affiliation(s)
| | - Rachel Gilroy
- Quadram Institute Bioscience, Norwich, Norfolk, United Kingdom
| | - Maria Getino
- NIHR Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Department of Infectious Disease, Imperial College London, London, United Kingdom,Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Ebenezer Foster-Nyarko
- Quadram Institute Bioscience, Norwich, Norfolk, United Kingdom,Department of Infection Biology, London School of Hygiene & Tropical Medicine, University of London, London, United Kingdom
| | - Arnoud H.M. van Vliet
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Roberto M. La Ragione
- Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, United Kingdom,Department of Microbial Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, Surrey, United Kingdom
| | - Mark J. Pallen
- Quadram Institute Bioscience, Norwich, Norfolk, United Kingdom,Department of Pathology and Infectious Diseases, School of Veterinary Medicine, University of Surrey, Guildford, Surrey, United Kingdom,School of Biological Sciences, University of East Anglia, Norwich, Norfolk, United Kingdom
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2
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Zhang CZ, Zhang Y, Ding XM, Lin XL, Lian XL, Trampari E, Thomson NM, Ding HZ, Webber MA, Jiang HX. Emergence of ciprofloxacin heteroresistance in foodborne Salmonella enterica serovar Agona. J Antimicrob Chemother 2021; 75:2773-2779. [PMID: 32747937 DOI: 10.1093/jac/dkaa288] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 06/03/2020] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Bacterial heteroresistance has been increasingly identified as an important phenomenon for many antibiotic/bacterium combinations. OBJECTIVES To investigate ciprofloxacin heteroresistance in Salmonella and characterize mechanisms contributing to ciprofloxacin heteroresistance. METHODS Ciprofloxacin-heteroresistant Salmonella were identified by population analysis profiling (PAP). Target mutations and the presence of PMQR genes were detected using PCR and sequencing. Expression of acrB, acrF and qnrS was conducted by quantitative RT-PCR. Competition ability and virulence were also compared using pyrosequencing, blue/white screening, adhesion and invasion assays and a Galleria model. Two subpopulations were whole-genome sequenced using Oxford Nanopore and Illumina platforms. RESULTS PAP identified one Salmonella from food that yielded a subpopulation demonstrating heteroresistance to ciprofloxacin at a low frequency (10-9 to 10-7). WGS and PFGE analyses confirmed that the two subpopulations were isogenic, with six SNPs and two small deletions distinguishing the resistant from the susceptible. Both subpopulations possessed a T57S substitution in ParC and carried qnrS. The resistant subpopulation was distinguished by overexpression of acrB and acrF, a deletion within rsxC and altered expression of soxS. The resistant population had a competitive advantage against the parental population when grown in the presence of bile salts but was attenuated in the adhesion and invasion of human intestinal cells. CONCLUSIONS We determined that heteroresistance resulted from a combination of mutations in fluoroquinolone target genes and overexpression of efflux pumps associated with a deletion in rsxC. This study warns that ciprofloxacin heteroresistance exists in Salmonella in the food chain and highlights the necessity for careful interpretation of antibiotic susceptibility.
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Affiliation(s)
- Chuan-Zhen Zhang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.,Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ, UK
| | - Yan Zhang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xiao-Min Ding
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xiao-Ling Lin
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Xin-Lei Lian
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Eleftheria Trampari
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ, UK
| | - Nicholas M Thomson
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ, UK
| | - Huan-Zhong Ding
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
| | - Mark A Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk NR4 7UQ, UK.,Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7UH, UK
| | - Hong-Xia Jiang
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
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3
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Page AJ, Mather AE, Le-Viet T, Meader EJ, Alikhan NF, Kay GL, de Oliveira Martins L, Aydin A, Baker DJ, Trotter AJ, Rudder S, Tedim AP, Kolyva A, Stanley R, Yasir M, Diaz M, Potter W, Stuart C, Meadows L, Bell A, Gutierrez AV, Thomson NM, Adriaenssens EM, Swingler T, Gilroy RAJ, Griffith L, Sethi DK, Aggarwal D, Brown CS, Davidson RK, Kingsley RA, Bedford L, Coupland LJ, Charles IG, Elumogo N, Wain J, Prakash R, Webber MA, Smith SJL, Chand M, Dervisevic S, O’Grady J. Large-scale sequencing of SARS-CoV-2 genomes from one region allows detailed epidemiology and enables local outbreak management. Microb Genom 2021; 7:000589. [PMID: 34184982 PMCID: PMC8461472 DOI: 10.1099/mgen.0.000589] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 04/19/2021] [Indexed: 01/28/2023] Open
Abstract
The COVID-19 pandemic has spread rapidly throughout the world. In the UK, the initial peak was in April 2020; in the county of Norfolk (UK) and surrounding areas, which has a stable, low-density population, over 3200 cases were reported between March and August 2020. As part of the activities of the national COVID-19 Genomics Consortium (COG-UK) we undertook whole genome sequencing of the SARS-CoV-2 genomes present in positive clinical samples from the Norfolk region. These samples were collected by four major hospitals, multiple minor hospitals, care facilities and community organizations within Norfolk and surrounding areas. We combined clinical metadata with the sequencing data from regional SARS-CoV-2 genomes to understand the origins, genetic variation, transmission and expansion (spread) of the virus within the region and provide context nationally. Data were fed back into the national effort for pandemic management, whilst simultaneously being used to assist local outbreak analyses. Overall, 1565 positive samples (172 per 100 000 population) from 1376 cases were evaluated; for 140 cases between two and six samples were available providing longitudinal data. This represented 42.6 % of all positive samples identified by hospital testing in the region and encompassed those with clinical need, and health and care workers and their families. In total, 1035 cases had genome sequences of sufficient quality to provide phylogenetic lineages. These genomes belonged to 26 distinct global lineages, indicating that there were multiple separate introductions into the region. Furthermore, 100 genetically distinct UK lineages were detected demonstrating local evolution, at a rate of ~2 SNPs per month, and multiple co-occurring lineages as the pandemic progressed. Our analysis: identified a discrete sublineage associated with six care facilities; found no evidence of reinfection in longitudinal samples; ruled out a nosocomial outbreak; identified 16 lineages in key workers which were not in patients, indicating infection control measures were effective; and found the D614G spike protein mutation which is linked to increased transmissibility dominates the samples and rapidly confirmed relatedness of cases in an outbreak at a food processing facility. The large-scale genome sequencing of SARS-CoV-2-positive samples has provided valuable additional data for public health epidemiology in the Norfolk region, and will continue to help identify and untangle hidden transmission chains as the pandemic evolves.
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Affiliation(s)
- Andrew J. Page
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Alison E. Mather
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Thanh Le-Viet
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Emma J. Meader
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | | | - Gemma L. Kay
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | | | - Alp Aydin
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - David J. Baker
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Alexander J. Trotter
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Steven Rudder
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Ana P. Tedim
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- Grupo de Investigación Biomédica en Sepsis - BioSepsis, Hospital Universitario Rio Hortega/Instituto de Investigación Biomédica de Salamanca (IBSAL), Valladolid/Salamanca, Spain
| | - Anastasia Kolyva
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Rachael Stanley
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Muhammad Yasir
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Maria Diaz
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Will Potter
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Claire Stuart
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Lizzie Meadows
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Andrew Bell
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | | | | | | | - Tracey Swingler
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | | | - Luke Griffith
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Dheeraj K. Sethi
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Dinesh Aggarwal
- Public Health England, 61 Colindale Ave., London, NW9 5EQ, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
- Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
| | - Colin S. Brown
- Public Health England, 61 Colindale Ave., London, NW9 5EQ, UK
| | - Rose K. Davidson
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Robert A. Kingsley
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Luke Bedford
- Ipswich Hospital, Heath Road, Ipswich, IP4 5PD, UK
| | | | - Ian G. Charles
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Ngozi Elumogo
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - John Wain
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Reenesh Prakash
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Mark A. Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | | | - Meera Chand
- Public Health England, 61 Colindale Ave., London, NW9 5EQ, UK
| | - Samir Dervisevic
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Justin O’Grady
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - The COVID-19 Genomics UK (COG-UK) Consortium
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
- Grupo de Investigación Biomédica en Sepsis - BioSepsis, Hospital Universitario Rio Hortega/Instituto de Investigación Biomédica de Salamanca (IBSAL), Valladolid/Salamanca, Spain
- Public Health England, 61 Colindale Ave., London, NW9 5EQ, UK
- Department of Medicine, University of Cambridge, Cambridge, UK
- Cambridge University Hospital NHS Foundation Trust, Cambridge, UK
- Wellcome Sanger Institute, Hinxton, Cambridge, UK
- Ipswich Hospital, Heath Road, Ipswich, IP4 5PD, UK
- Public Health, County Hall, Martineau Lane, Norwich, NR1 2DH, UK
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4
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Baker DJ, Aydin A, Le-Viet T, Kay GL, Rudder S, de Oliveira Martins L, Tedim AP, Kolyva A, Diaz M, Alikhan NF, Meadows L, Bell A, Gutierrez AV, Trotter AJ, Thomson NM, Gilroy R, Griffith L, Adriaenssens EM, Stanley R, Charles IG, Elumogo N, Wain J, Prakash R, Meader E, Mather AE, Webber MA, Dervisevic S, Page AJ, O'Grady J. CoronaHiT: high-throughput sequencing of SARS-CoV-2 genomes. Genome Med 2021; 13:21. [PMID: 33563320 PMCID: PMC7871948 DOI: 10.1186/s13073-021-00839-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 01/26/2021] [Indexed: 01/15/2023] Open
Abstract
We present CoronaHiT, a platform and throughput flexible method for sequencing SARS-CoV-2 genomes (≤ 96 on MinION or > 96 on Illumina NextSeq) depending on changing requirements experienced during the pandemic. CoronaHiT uses transposase-based library preparation of ARTIC PCR products. Method performance was demonstrated by sequencing 2 plates containing 95 and 59 SARS-CoV-2 genomes on nanopore and Illumina platforms and comparing to the ARTIC LoCost nanopore method. Of the 154 samples sequenced using all 3 methods, ≥ 90% genome coverage was obtained for 64.3% using ARTIC LoCost, 71.4% using CoronaHiT-ONT and 76.6% using CoronaHiT-Illumina, with almost identical clustering on a maximum likelihood tree. This protocol will aid the rapid expansion of SARS-CoV-2 genome sequencing globally.
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Affiliation(s)
- Dave J Baker
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Alp Aydin
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Thanh Le-Viet
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Gemma L Kay
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Steven Rudder
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | | | - Ana P Tedim
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- Grupo de Investigación Biomédica en Sepsis - BioSepsis. Hospital Universitario Rio Hortega/Instituto de Investigación Biomédica de Salamanca (IBSAL), Valladolid/Salamanca, Spain
| | - Anastasia Kolyva
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Maria Diaz
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | | | - Lizzie Meadows
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Andrew Bell
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | | | - Alexander J Trotter
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Nicholas M Thomson
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Rachel Gilroy
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
| | - Luke Griffith
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | | | - Rachael Stanley
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Ian G Charles
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Ngozi Elumogo
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - John Wain
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Reenesh Prakash
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Emma Meader
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Alison E Mather
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Mark A Webber
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK
| | - Samir Dervisevic
- Norfolk and Norwich University Hospital, Colney Lane, Norwich, NR4 7UY, UK
| | - Andrew J Page
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK.
| | - Justin O'Grady
- Quadram Institute Bioscience, Norwich Research Park, Norwich, NR4 7UQ, UK.
- University of East Anglia, Norwich Research Park, Norwich, NR4 7TJ, UK.
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5
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Foster-Nyarko E, Alikhan NF, Ravi A, Thomson NM, Jarju S, Kwambana-Adams BA, Secka A, O’Grady J, Antonio M, Pallen MJ. Genomic diversity of Escherichia coli isolates from backyard chickens and guinea fowl in the Gambia. Microb Genom 2021; 7:mgen000484. [PMID: 33253086 PMCID: PMC8115903 DOI: 10.1099/mgen.0.000484] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 11/09/2020] [Indexed: 01/21/2023] Open
Abstract
Chickens and guinea fowl are commonly reared in Gambian homes as affordable sources of protein. Using standard microbiological techniques, we obtained 68 caecal isolates of Escherichia coli from 10 chickens and 9 guinea fowl in rural Gambia. After Illumina whole-genome sequencing, 28 sequence types were detected in the isolates (4 of them novel), of which ST155 was the most common (22/68, 32 %). These strains span four of the eight main phylogroups of E. coli, with phylogroups B1 and A being most prevalent. Nearly a third of the isolates harboured at least one antimicrobial resistance gene, while most of the ST155 isolates (14/22, 64 %) encoded resistance to ≥3 classes of clinically relevant antibiotics, as well as putative virulence factors, suggesting pathogenic potential in humans. Furthermore, hierarchical clustering revealed that several Gambian poultry strains were closely related to isolates from humans. Although the ST155 lineage is common in poultry from Africa and South America, the Gambian ST155 isolates belong to a unique cgMLST cluster comprising closely related (38-39 alleles differences) isolates from poultry and livestock from sub-Saharan Africa - suggesting that strains can be exchanged between poultry and livestock in this setting. Continued surveillance of E. coli and other potential pathogens in rural backyard poultry from sub-Saharan Africa is warranted.
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Affiliation(s)
- Ebenezer Foster-Nyarko
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Boulevard Road, Fajara, Gambia
| | | | - Anuradha Ravi
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | | | - Sheikh Jarju
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Boulevard Road, Fajara, Gambia
| | - Brenda A. Kwambana-Adams
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Boulevard Road, Fajara, Gambia
- NIHR Global Health Research Unit on Mucosal Pathogens, Division of Infection and Immunity, University College London, London, UK
| | - Arss Secka
- West Africa Livestock Innovation Centre (WALIC), MB 14, Banjul, Gambia
| | - Justin O’Grady
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | - Martin Antonio
- Medical Research Council Unit The Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Boulevard Road, Fajara, Gambia
- Warwick Medical School, University of Warwick, Coventry, UK
| | - Mark John Pallen
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
- School of Veterinary Medicine, University of Surrey, Guildford, Surrey, UK
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6
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Thomson NM, Pallen MJ. Restoration of wild-type motility to flagellin-knockout Escherichia coli by varying promoter, copy number and induction strength in plasmid-based expression of flagellin. Curr Res Biotechnol 2021; 2:45-52. [PMID: 33381753 PMCID: PMC7758877 DOI: 10.1016/j.crbiot.2020.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Flagellin is the major constituent of the flagellar filament and faithful restoration of wild-type motility to flagellin mutants may be beneficial for studies of flagellar biology and biotechnological exploitation of the flagellar system. However, gene complementation studies often fail to report whether true wild-type motility was restored by expressing flagellin from a plasmid. Therefore, we explored the restoration of motility by flagellin expressed from a variety of combinations of promoter, plasmid copy number and induction strength. Motility was only partially (~50%) restored using the tightly regulated rhamnose promoter due to weak flagellin gene expression, but wild-type motility was regained with the T5 promoter, which, although leaky, allowed titration of induction strength. The endogenous E. coli flagellin promoter also restored wild-type motility. However, flagellin gene transcription levels increased 3.1–27.9-fold when wild-type motility was restored, indicating disturbances in the flagellar regulatory mechanisms. Motility was little affected by plasmid copy number when dependent on inducible promoters. However, plasmid copy number was important when expression was controlled by the native E. coli flagellin promoter. Motility was poorly correlated with flagellin transcription levels, but strongly correlated with the amount of flagellin associated with the flagellar filament, suggesting that excess monomers are either not exported or not assembled into filaments. This study provides a useful reference for further studies of flagellar function and a simple blueprint for similar studies with other proteins. Restoration of motility to flagellin-knockout E. coli depends on choice of promoter. Plasmid copy number is important when using the natural flagellin promoter. For inducible promoters, induction strength is more important than copy number. Large increase in flagellin transcription but not flagella-associated protein. Plasmid-based expression interrupts flagellin expression control mechanisms.
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Affiliation(s)
- Nicholas M Thomson
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, United Kingdom
| | - Mark J Pallen
- Quadram Institute Bioscience, Norwich Research Park, Norwich NR4 7UQ, United Kingdom
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7
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Holden ER, Wickham GJ, Webber MA, Thomson NM, Trampari E. Donor plasmids for phenotypically neutral chromosomal gene insertions in Enterobacteriaceae. Microbiology (Reading) 2020; 166:1115-1120. [PMID: 33226934 DOI: 10.1099/mic.0.000994] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Recombineering using bacteriophage lambda Red recombinase (λ-Red) uses homologous recombination to manipulate bacterial genomes and is commonly applied to disrupt genes to elucidate their function. This is often followed by the introduction of a wild-type copy of the gene on a plasmid to complement its function. This is often not, however, at a native copy number and the introduction of a chromosomal version of a gene can be a desirable solution to provide wild-type copy expression levels of an allele in trans. Here, we present a simple methodology based on the λ-Red-based 'gene doctoring' technique, where we developed tools used for chromosomal tagging in a conserved locus downstream of glmS and found no impact on a variety of important phenotypes. The tools described provide an easy, quick and inexpensive method of chromosomal modification for the creation of a library of insertion mutants to study gene function.
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Affiliation(s)
- Emma R Holden
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Gregory J Wickham
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Mark A Webber
- Medical School, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TJ, UK.,Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Nicholas M Thomson
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Eleftheria Trampari
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
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8
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Abstract
Background Gene doctoring is an efficient recombination-based genetic engineering approach to mutagenesis of the bacterial chromosome that combines the λ-Red recombination system with a suicide donor plasmid that is cleaved in vivo to generate linear DNA fragments suitable for recombination. The use of a suicide donor plasmid makes Gene Doctoring more efficient than other recombineering technologies. However, generation of donor plasmids typically requires multiple cloning and screening steps. Results We constructed a simplified acceptor plasmid, called pDOC-GG, for the assembly of multiple DNA fragments precisely and simultaneously to form a donor plasmid using Golden Gate assembly. Successful constructs can easily be identified through blue-white screening. We demonstrated proof of principle by inserting a gene for green fluorescent protein into the chromosome of Escherichia coli. We also provided related genetic parts to assist in the construction of mutagenesis cassettes with a tetracycline-selectable marker. Conclusions Our plasmid greatly simplifies the construction of Gene Doctoring donor plasmids and allows for the assembly of complex, multi-part insertion or deletion cassettes with a free choice of target sites and selection markers. The tools we developed are applicable to gene editing for a wide variety of purposes in Enterobacteriaceae and potentially in other diverse bacterial families.
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Affiliation(s)
- Nicholas M Thomson
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Chuanzhen Zhang
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK.,National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China.,Guangdong Key Laboratory for Veterinary Drug Development and Safety evaluation, College of Veterinary Medicine, South China Agricultural University, Guangzhou, 510642, China
| | - Eleftheria Trampari
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Mark J Pallen
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK. .,School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk, NR4 7TU, UK. .,School of Veterinary Medicine, University of Surrey, Daphne Jackson Road, Guildford, Surrey, GU2 7AL, UK.
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9
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Foster-Nyarko E, Alikhan NF, Ravi A, Thilliez G, Thomson NM, Baker D, Kay G, Cramer JD, O’Grady J, Antonio M, Pallen MJ. Genomic diversity of Escherichia coli isolates from non-human primates in the Gambia. Microb Genom 2020; 6:mgen000428. [PMID: 32924917 PMCID: PMC7643976 DOI: 10.1099/mgen.0.000428] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 08/13/2020] [Indexed: 01/27/2023] Open
Abstract
Increasing contact between humans and non-human primates provides an opportunity for the transfer of potential pathogens or antimicrobial resistance between host species. We have investigated genomic diversity and antimicrobial resistance in Escherichia coli isolates from four species of non-human primates in the Gambia: Papio papio (n=22), Chlorocebus sabaeus (n=14), Piliocolobus badius (n=6) and Erythrocebus patas (n=1). We performed Illumina whole-genome sequencing on 101 isolates from 43 stools, followed by nanopore long-read sequencing on 11 isolates. We identified 43 sequence types (STs) by the Achtman scheme (ten of which are novel), spanning five of the eight known phylogroups of E. coli. The majority of simian isolates belong to phylogroup B2 - characterized by strains that cause human extraintestinal infections - and encode factors associated with extraintestinal disease. A subset of the B2 strains (ST73, ST681 and ST127) carry the pks genomic island, which encodes colibactin, a genotoxin associated with colorectal cancer. We found little antimicrobial resistance and only one example of multi-drug resistance among the simian isolates. Hierarchical clustering showed that simian isolates from ST442 and ST349 are closely related to isolates recovered from human clinical cases (differences in 50 and 7 alleles, respectively), suggesting recent exchange between the two host species. Conversely, simian isolates from ST73, ST681 and ST127 were distinct from human isolates, while five simian isolates belong to unique core-genome ST complexes - indicating novel diversity specific to the primate niche. Our results are of planetary health importance, considering the increasing contact between humans and wild non-human primates.
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Affiliation(s)
- Ebenezer Foster-Nyarko
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
- Medical Research Council Unit the Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Boulevard Road, Fajara, Gambia
| | | | - Anuradha Ravi
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | - Gaëtan Thilliez
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | | | - David Baker
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | - Gemma Kay
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | | | - Justin O’Grady
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
| | - Martin Antonio
- Medical Research Council Unit the Gambia at the London School of Hygiene and Tropical Medicine, Atlantic Boulevard Road, Fajara, Gambia
- Microbiology and Infection Unit, Warwick Medical School, University of Warwick, Coventry, UK
| | - Mark J. Pallen
- Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, UK
- School of Veterinary Medicine, University of Surrey, Guildford, Surrey, UK
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10
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Ravi A, Halstead FD, Bamford A, Casey A, Thomson NM, van Schaik W, Snelson C, Goulden R, Foster-Nyarko E, Savva GM, Whitehouse T, Pallen MJ, Oppenheim BA. Loss of microbial diversity and pathogen domination of the gut microbiota in critically ill patients. Microb Genom 2019; 5. [PMID: 31526447 PMCID: PMC6807385 DOI: 10.1099/mgen.0.000293] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Among long-stay critically ill patients in the adult intensive care unit (ICU), there are often marked changes in the complexity of the gut microbiota. However, it remains unclear whether such patients might benefit from enhanced surveillance or from interventions targeting the gut microbiota or the pathogens therein. We therefore undertook a prospective observational study of 24 ICU patients, in which serial faecal samples were subjected to shotgun metagenomic sequencing, phylogenetic profiling and microbial genome analyses. Two-thirds of the patients experienced a marked drop in gut microbial diversity (to an inverse Simpson’s index of <4) at some stage during their stay in the ICU, often accompanied by the absence or loss of potentially beneficial bacteria. Intravenous administration of the broad-spectrum antimicrobial agent meropenem was significantly associated with loss of gut microbial diversity, but the administration of other antibiotics, including piperacillin/tazobactam, failed to trigger statistically detectable changes in microbial diversity. In three-quarters of ICU patients, we documented episodes of gut domination by pathogenic strains, with evidence of cryptic nosocomial transmission of Enterococcus faecium. In some patients, we also saw an increase in the relative abundance of apparent commensal organisms in the gut microbiome, including the archaeal species Methanobrevibacter smithii. In conclusion, we have documented a dramatic absence of microbial diversity and pathogen domination of the gut microbiota in a high proportion of critically ill patients using shotgun metagenomics.
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Affiliation(s)
- Anuradha Ravi
- Quadram Institute Bioscience and University of East Anglia, Norwich, NR4 7UA, UK
| | - Fenella D Halstead
- Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2GW, UK.,NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, B15 2GW, UK
| | - Amy Bamford
- Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2GW, UK.,NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, B15 2GW, UK
| | - Anna Casey
- Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2GW, UK.,NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, B15 2GW, UK
| | - Nicholas M Thomson
- Quadram Institute Bioscience and University of East Anglia, Norwich, NR4 7UA, UK
| | - Willem van Schaik
- Institute of Microbiology and Infection, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Catherine Snelson
- Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2GW, UK
| | | | | | - George M Savva
- Quadram Institute Bioscience and University of East Anglia, Norwich, NR4 7UA, UK
| | - Tony Whitehouse
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK.,Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2GW, UK
| | - Mark J Pallen
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TU, UK.,Quadram Institute Bioscience and University of East Anglia, Norwich, NR4 7UA, UK.,School of Veterinary Medicine, University of Surrey, Daphne Jackson Rd, Guildford GU2 7AL, UK
| | - Beryl A Oppenheim
- Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, B15 2GW, UK.,NIHR Surgical Reconstruction and Microbiology Research Centre, Queen Elizabeth Hospital, Birmingham, B15 2GW, UK
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11
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Thomson NM, Ferreira JL, Matthews-Palmer TR, Beeby M, Pallen MJ. Giant flagellins form thick flagellar filaments in two species of marine γ-proteobacteria. PLoS One 2018; 13:e0206544. [PMID: 30462661 PMCID: PMC6248924 DOI: 10.1371/journal.pone.0206544] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/15/2018] [Indexed: 01/04/2023] Open
Abstract
Flagella, the primary means of motility in bacteria, are helical filaments that function as microscopic propellers composed of thousands of copies of the protein flagellin. Here, we show that many bacteria encode “giant” flagellins, greater than a thousand amino acids in length, and that two species that encode giant flagellins, the marine γ-proteobacteria Bermanella marisrubri and Oleibacter marinus, produce monopolar flagellar filaments considerably thicker than filaments composed of shorter flagellin monomers. We confirm that the flagellum from B. marisrubri is built from its giant flagellin. Phylogenetic analysis reveals that the mechanism of evolution of giant flagellins has followed a stepwise process involving an internal domain duplication followed by insertion of an additional novel insert. This work illustrates how “the” bacterial flagellum should not be seen as a single, idealised structure, but as a continuum of evolved machines adapted to a range of niches.
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Affiliation(s)
| | - Josie L. Ferreira
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | | | - Morgan Beeby
- Department of Life Sciences, Imperial College London, London, United Kingdom
- * E-mail:
| | - Mark J. Pallen
- Quadram Institute, Norwich Research Park, Norwich, Norfolk, United Kingdom
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12
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Thomson NM, Shirai T, Chiapello M, Kondo A, Mukherjee KJ, Sivaniah E, Numata K, Summers DK. Efficient 3-Hydroxybutyrate Production by QuiescentEscherichia coliMicrobial Cell Factories is Facilitated by Indole-Induced Proteomic and Metabolomic Changes. Biotechnol J 2018; 13:e1700571. [DOI: 10.1002/biot.201700571] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Revised: 12/09/2017] [Indexed: 01/05/2023]
Affiliation(s)
- Nicholas M. Thomson
- Enzyme Research Team; RIKEN Centre for Sustainable Resource Science; Wako-shi 351-0198 Japan
- Department of Genetics; University of Cambridge; Cambridge CB2 3EH UK
| | - Tomokazu Shirai
- Cell Factory Research Team; RIKEN Centre for Sustainable Resource Science; Yokohama 230-0045 Japan
| | - Marco Chiapello
- Cambridge Centre for Proteomics; University of Cambridge; Cambridge CB2 1QR UK
| | - Akihiko Kondo
- Cell Factory Research Team; RIKEN Centre for Sustainable Resource Science; Yokohama 230-0045 Japan
| | | | - Easan Sivaniah
- Institute for Integrated Cell-Material Sciences (iCeMS); Kyoto University; Kyoto 606-8501 Japan
| | - Keiji Numata
- Enzyme Research Team; RIKEN Centre for Sustainable Resource Science; Wako-shi 351-0198 Japan
| | - David K. Summers
- Department of Genetics; University of Cambridge; Cambridge CB2 3EH UK
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13
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Thomson NM, Sangiambut S, Ushimaru K, Sivaniah E, Tsuge T. Poly(hydroxyalkanoate) Generation from Nonchiral Substrates Using Multiple Enzyme Immobilizations on Peptide Nanofibers. ACS Biomater Sci Eng 2016; 3:3076-3082. [DOI: 10.1021/acsbiomaterials.6b00329] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Nicholas M. Thomson
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Smith Sangiambut
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Kazunori Ushimaru
- Department
of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
| | - Easan Sivaniah
- Cavendish
Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
- Institute
for Integrated Cell-Material Sciences, Kyoto University, Yoshida Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takeharu Tsuge
- Department
of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
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14
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Thomson NM, Singer R, Seibert KD, Luciani CV, Srivastava S, Kiesman WF, Irdam EA, Lepore JV, Schenck L. Case Studies in the Development of Drug Substance Control Strategies. Org Process Res Dev 2015. [DOI: 10.1021/acs.oprd.5b00146] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicholas M. Thomson
- Chemical
Research and Development, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340, United States
| | - Robert Singer
- Chemical
Research and Development, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340, United States
| | - Kevin D. Seibert
- Small
Molecule Design and Development, Eli Lilly and Co., Lilly Technology Center, Indianapolis, Indiana 46285, United States
| | - Carla V. Luciani
- Small
Molecule Design and Development, Eli Lilly and Co., Lilly Technology Center, Indianapolis, Indiana 46285, United States
| | - Sushil Srivastava
- Chemical
Development, Bristol-Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - William F. Kiesman
- Chemical
Process Research and Development, Biogen, 14 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Erwin A. Irdam
- Chemical
Process Research and Development, Biogen, 14 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - John V. Lepore
- Chemical
Process Development and Commercialization, Merck, 126 East Lincoln
Avenue, Rahway, New Jersey 07065, United States
| | - Luke Schenck
- Chemical
Process Development and Commercialization, Merck, 126 East Lincoln
Avenue, Rahway, New Jersey 07065, United States
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15
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Affiliation(s)
- Stéphane Caron
- Chemical R&D, Pfizer Worldwide Research & Development, Groton, Connecticut 06340, United States
| | - Nicholas M. Thomson
- Chemical R&D, Pfizer Worldwide Research & Development, Groton, Connecticut 06340, United States
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16
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Thomson NM, Seibert KD, Tummala S, Bordawekar S, Kiesman WF, Irdam EA, Phenix B, Kumke D. Case Studies in the Applicability of Drug Substance Design Spaces Developed on the Laboratory Scale to Commercial Manufacturing. Org Process Res Dev 2014. [DOI: 10.1021/op500187u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicholas M. Thomson
- Chemical
Research and Development, Pfizer Inc., Eastern Point Road, Groton, Connecticut 06340, United States
| | - Kevin D. Seibert
- Small
Molecule Design and Development, Eli Lilly and Co., Lilly Technology Center, Indianapolis, Indiana 46285, United States
| | - Srinivas Tummala
- Chemical
Development, Bristol-Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Shailendra Bordawekar
- Process
Research and Development, AbbVie, 1 North Waukegan Road, North Chicago, Illinois 60064, United States
| | - William F. Kiesman
- Chemical
Process Research and Development, Biogen Idec, 14 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Erwin A. Irdam
- Chemical
Process Research and Development, Biogen Idec, 14 Cambridge Center, Cambridge, Massachusetts 02142, United States
| | - Brian Phenix
- Chemical
Development, Vertex Pharmaceuticals Incorporated, 50 Northern Avenue, Boston, Massachusetts 02210, United States
| | - Daniel Kumke
- Chemical
Process Development and Commercialization, Merck, 126 East Lincoln
Avenue, Rahway, New Jersey 07065, United States
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17
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Hiroe A, Hyakutake M, Thomson NM, Sivaniah E, Tsuge T. Endogenous ethanol affects biopolyester molecular weight in recombinant Escherichia coli. ACS Chem Biol 2013; 8:2568-76. [PMID: 24041146 DOI: 10.1021/cb400465p] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In biopolyester synthesis, polyhydroxyalkanoate (PHA) synthase (PhaC) catalyzes the polymerization of PHA in bacterial cells, followed by a chain transfer (CT) reaction in which the PHA polymer chain is transferred from PhaC to a CT agent. Accordingly, the frequency of CT reaction determines PHA molecular weight. Previous studies have shown that exogenous alcohols are effective CT agents. This study aimed to clarify the effect of endogenous ethanol as a CT agent for poly[(R)-3-hydroxybutyrate] [P(3HB)] synthesis in recombinant Escherichia coli, by comparing with that of exogenous ethanol. Ethanol supplementation to the culture medium reduced P(3HB) molecular weights by up to 56% due to ethanol-induced CT reaction. NMR analysis of P(3HB) polymers purified from the culture supplemented with (13)C-labeled ethanol showed the formation of a covalent bond between ethanol and P(3HB) chain at the carboxyl end. Cultivation without ethanol supplementation resulted in the reduction of P(3HB) molecular weight with increasing host-produced ethanol depending on culture aeration. On the other hand, production in recombinant BW25113(ΔadhE), an alcohol dehydrogenase deletion strain, resulted in a 77% increase in molecular weight. Analysis of five E. coli strains revealed that the estimated number of CT reactions was correlated with ethanol production. These results demonstrate that host-produced ethanol acts as an equally effective CT agent as exogenous ethanol, and the control of ethanol production is important to regulate the PHA molecular weight.
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Affiliation(s)
- Ayaka Hiroe
- Department
of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
| | - Manami Hyakutake
- Department
of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
| | - Nicholas M. Thomson
- Biological and
Soft Systems, Cavendish Laboratory, University of Cambridge, 19 JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Easan Sivaniah
- Biological and
Soft Systems, Cavendish Laboratory, University of Cambridge, 19 JJ Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Takeharu Tsuge
- Department
of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8502, Japan
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18
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Sangiambut S, Channon K, Thomson NM, Sato S, Tsuge T, Doi Y, Sivaniah E. A robust route to enzymatically functional, hierarchically self-assembled peptide frameworks. Adv Mater 2013; 25:2661-2665. [PMID: 23341342 DOI: 10.1002/adma.201204127] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/21/2012] [Indexed: 06/01/2023]
Abstract
The addition of enzyme biofunctionality to self-assembling peptide nanofibers is challenging since such additions can inhibit functionality or self-assembly. We introduce a method for peptide nanofiber enzyme functionalization, demonstrated by the attachment of a polymerization synthase to peptide nanofibers. The enzyme generates a biocompatible, biodegradable biopolyester coat on the fibers with applicablity in medical engineering. This approach provides a template for generation of functional bionanomaterials.
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Affiliation(s)
- S Sangiambut
- Biological and Soft Systems, Cavendish Laboratory, University of Cambridge, CB3 0HE, UK
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19
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de Koning PD, Castro N, Gladwell IR, Morrison NA, Moses IB, Panesar MS, Pettman AJ, Thomson NM. Development of a Potential Manufacturing Route to PF-00610355: A Novel Inhaled β2-Adrenoreceptor Agonist. Org Process Res Dev 2011. [DOI: 10.1021/op2002408] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pieter D. de Koning
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Nieves Castro
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Iain R. Gladwell
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Natalie A. Morrison
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Ian B. Moses
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Maninder S. Panesar
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Alan J. Pettman
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Nicholas M. Thomson
- Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
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20
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de Koning PD, Gladwell IR, Moses IB, Panesar MS, Pettman AJ, Thomson NM. Development of an Enabling Route to PF-00610355: A Novel Inhaled β2-Adrenoreceptor Agonist. Org Process Res Dev 2011. [DOI: 10.1021/op2001904] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Pieter D. de Koning
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Iain R. Gladwell
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Ian B. Moses
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Maninder S. Panesar
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Alan J. Pettman
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Nicholas M. Thomson
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
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21
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de Koning PD, Gladwell IR, Morrison NA, Moses IB, Panesar MS, Pettman AJ, Thomson NM, Yazbeck DR. Enzymatic Desymmetrization Route to Ethyl [3-(2-Amino-2-methylpropyl)phenyl]acetate. Org Process Res Dev 2011. [DOI: 10.1021/op200108k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Pieter D. de Koning
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Iain R. Gladwell
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Natalie A. Morrison
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Ian B. Moses
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Maninder S. Panesar
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Alan J. Pettman
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Nicholas M. Thomson
- Research API, Pfizer Global Research and Development, Sandwich Laboratories, Ramsgate Road, Sandwich, Kent CT13 9NJ, U.K
| | - Daniel R. Yazbeck
- Pfizer Global Research and Development, 10578 Science Center Drive, San Diego, California 92121, United States
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22
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Thomson NM, Channon K, Mokhtar NA, Staniewicz L, Rai R, Roy I, Sato S, Tsuge T, Donald AM, Summers D, Sivaniah E. Imaging internal features of whole, unfixed bacteria. Scanning 2011; 33:59-68. [PMID: 21344457 DOI: 10.1002/sca.20221] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 01/21/2011] [Indexed: 05/30/2023]
Abstract
Wet scanning-transmission electron microscopy (STEM) is a technique that allows high-resolution transmission imaging of biological samples in a hydrated state, with minimal sample preparation. However, it has barely been used for the study of bacterial cells. In this study, we present an analysis of the advantages and disadvantages of wet STEM compared with standard transmission electron microscopy (TEM). To investigate the potential applications of wet STEM, we studied the growth of polyhydroxyalkanoate and triacylglycerol carbon storage inclusions. These were easily visible inside cells, even in the early stages of accumulation. Although TEM produces higher resolution images, wet STEM is useful when preservation of the sample is important or when studying the relative sizes of different features, since samples do not need to be sectioned. Furthermore, under carefully selected conditions, it may be possible to maintain cell viability, enabling new types of experiments to be carried out. To our knowledge, internal features of bacterial cells have not been imaged previously by this technique.
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Affiliation(s)
- Nicholas M Thomson
- Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom
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Teteris SA, Menahem SA, Perry G, Maguire JA, Dowling JP, Langham RG, Thomson NM, Stein AN. Dysregulated growth factor gene expression is associated with tubulointerstitial apoptosis and renal dysfunction. Kidney Int 2007; 71:1044-53. [PMID: 17361117 DOI: 10.1038/sj.ki.5002176] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Chronic renal disease is characterized by declining renal function, loss of intrinsic renal cells, and their replacement with fibrotic tissue. This study investigates apoptosis and its regulation in the context of chronic renal disease. RNA was extracted from renal biopsies from patients with various forms of chronic renal disease. Expression of genes of the Bcl-2 family, death receptor pathway, and growth factors were measured by reverse-transcription real-time polymerase chain reaction. Apoptosis was detected by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling technique. Tubulointerstitial apoptosis was positively associated with tubulointerstitial injury and renal dysfunction and increased 2.3-fold per unit (U) increase in transforming growth factor beta(1) (TGFbeta(1)) mRNA (P<0.05). Conversely, a 1 U increase in epidermal growth factor (EGF) mRNA was associated with a 47% decrease in tubulointerstitial apoptosis (P<0.05). Tubulointerstitial injury was correlated with increased TGFbeta(1) and tumour necrosis factor alpha (TNFalpha) mRNA (P<0.005) and decreased EGF mRNA (P<0.05). Additionally, for a 10 U decrease in the glomerular filtration rate there was an estimated increase of 5 and 10% in TGFbeta(1) and TNFalpha mRNA, respectively (P<0.05), whereas EGF mRNA decreased by an estimated 15% (P<0.005). Therefore dysregulation of cytokine/growth factor expression plays a central role in the progression of chronic renal disease through contribution to renal cell loss, tubulointerstitial injury, and renal dysfunction.
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Affiliation(s)
- S A Teteris
- Department of Medicine, Central and Eastern Clinical School, Monash University, Prahran, Victoria, Australia
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24
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Pattenden G, Stoker DA, Thomson NM. Cascade radical-mediated cyclisations with conjugated ynone electrophores. An approach to the synthesis of steroids and other novel ring-fused polycyclic carbocycles. Org Biomol Chem 2007; 5:1776-88. [PMID: 17520147 DOI: 10.1039/b703373g] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A cascade radical-mediated Diels-Alder reaction with the iododienynone 16b produced the tricyclic ketone 17 (22%). By contrast, treatment of the substituted furans 36 and 47 with Bu(3)SnH-AIBN, instead led to the tetracycles 44 and 58 respectively, rather than the anticipated oestranes, i.e. 38 and 48. In a separate study, attempted cascade radical-mediated cyclisations from the ortho-aryl substituted iododienynones 72 and 73, leading to the ring-D aromatic steroid 7, instead gave the macrocyclic ketone 76 or the novel bridged tricycles 77/82, respectively, depending on whether benzene or heptane was used as solvent in the reactions.
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Affiliation(s)
- Gerald Pattenden
- School of Chemistry, The University of Nottingham, University Park, Nottingham, England, UK NG7 2RD.
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25
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Hayes CJ, Bradley DM, Thomson NM. An Efficient Enantioselective Synthesis of (2R)-Hydroxymethyl Glutamic Acid and an Approach to the (2R)-Hydroxymethyl-Substituted Sphingofungins. J Org Chem 2006; 71:2661-5. [PMID: 16555818 DOI: 10.1021/jo052408q] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have developed a short enantioselective synthesis of (2R)-hydroxymethyl glutamic acid (HMG) starting from Garner's aldehyde using an alkylidene carbene 1,5-CH insertion as a method to construct the quaternary stereocenter. A variety of conditions were examined for the oxidative cleavage of the key cyclopentene intermediate and we found that RuCl3/NaIO4 led directly to the desired amino bis-acid product. We were also able to show that oxidative cleavage of the cyclopentene 1,5-CH insertion product could be used to produce the amino acid-containing skeleton of the sphingofungin family of natural products.
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Affiliation(s)
- Christopher J Hayes
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom.
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26
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Ashcroft CP, Challenger S, Clifford D, Derrick AM, Hajikarimian Y, Slucock K, Silk TV, Thomson NM, Williams JR. An Efficient and Scalable Synthesis of the Endothelin Antagonists UK-350,926 and UK-349,862 Using a Dynamic Resolution Process. Org Process Res Dev 2005. [DOI: 10.1021/op050102f] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christopher P. Ashcroft
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Stephen Challenger
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - David Clifford
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Andrew M. Derrick
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Yousef Hajikarimian
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Keith Slucock
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Terry V. Silk
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Nicholas M. Thomson
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - John R. Williams
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
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27
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Jablonski P, Goh BL, Maguire J, Glogowski I, Howden BO, Thomson NM, Stein AN. Apoptosis and the expression of genes of the Bcl-2 family and TGF-beta1 in rat renal allografts transplanted after donor-specific blood transfusion. Transplant Proc 2005; 37:93-5. [PMID: 15808558 DOI: 10.1016/j.transproceed.2004.12.182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
UNLABELLED Factors involved in "operational" tolerance in animal models induced by recipient pre-treatment with donor-specific blood transfusion (DSBT) need elucidation. This study examined apoptosis, expression of genes of the Bcl-2 family and of TGF-beta(1) in isografts, rejecting and tolerant allografts. METHODS Adult inbred Dark Agouti (DA) kidneys were transplanted, with immediate nephrectomy of recipient kidneys, to (1) ALLO, inbred Albino Surgery (AS) rats; (2) DSBT ALLO, AS rats who received two DA blood transfusions under cover of cyclosporine prior to transplantation; or (3) ISO, DA rats. Grafts were retrieved on day 1, 3, or 5. Apoptosis was assessed by TUNEL. RNA was extracted and reverse transcribed to cDNA for quantification by real-time PCR, relative to the 18s housekeeping gene. RESULTS Apoptosis was negligible in ISO while it increased in allograft groups from day 1. On day 5, apoptosis in ALLO (114.0 +/- 30.6), involved renal tubular cells and leukocytes compared to DSBT ALLO (9.7 +/- 4.0) and ISO (0.9 +/- 0.3) involving leukocytes only. On day 1, DSBT ALLO had higher expression of Bax than ALLO or ISO. On day 3, DSBT ALLO and ALLO had higher TGF-beta(1) mRNA than ISO. On day 5, Bcl-2 expression was significantly decreased (P < .001) in ALLO compared to DSBT ALLO and ISO. Bad and Bid were higher in DSBT ALLO than in ALLO. TGF-beta(1) was higher in DSBT ALLO compared to ISO. CONCLUSIONS Decreased expression of anti-apoptotic Bcl-2 gene may be implicated in increased apoptosis in rejecting allograft while expression of pro-apoptotic genes may be involved in the establishment of operational tolerance.
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Affiliation(s)
- P Jablonski
- Monash University, Department of Medicine, The Alfred Hospital, Clayton, Australia.
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28
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Ashcroft CP, Challenger S, Derrick AM, Storey R, Thomson NM. Asymmetric Synthesis of an MMP-3 Inhibitor Incorporating a 2-Alkyl Succinate Motif. Org Process Res Dev 2003. [DOI: 10.1021/op034001y] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Christopher P. Ashcroft
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Stephen Challenger
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Andrew M. Derrick
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Richard Storey
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
| | - Nicholas M. Thomson
- Department of Chemical Research and Development, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent CT13 9NJ, United Kingdom
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29
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Bradley DM, Mapitse R, Thomson NM, Hayes CJ. Enantioselective synthesis of the excitatory amino acid (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid. J Org Chem 2002; 67:7613-7. [PMID: 12398480 DOI: 10.1021/jo025892v] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An enantioselective synthesis of the alpha,alpha-dialkyl-alpha-amino acid (1S,3R)-ACPD has been achieved using an alkylidene carbene 1,5-CH insertion reaction as a key step. The ketone cyclization precursor was synthesized from Garner's aldehyde in high yield via a Wittig homologation and subsequent catalytic hydrogenation. Treatment of the ketone with 1.2 equiv of lithio(trimethylsilyl)diazomethane in THF resulted in the formation of the corresponding cyclopentene-containing CH-insertion product in 62-69% yield in high enantiomeric excess. Subsequent functional group manipulation allowed the synthesis of the amino acid (1S,3R)-ACPD to be completed.
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Affiliation(s)
- Daniel M Bradley
- The School of Chemistry, University of Nottingham, University Park, UK
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30
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Langham RG, Kelly DJ, Cox AJ, Thomson NM, Holthöfer H, Zaoui P, Pinel N, Cordonnier DJ, Gilbert RE. Proteinuria and the expression of the podocyte slit diaphragm protein, nephrin, in diabetic nephropathy: effects of angiotensin converting enzyme inhibition. Diabetologia 2002; 45:1572-6. [PMID: 12436341 DOI: 10.1007/s00125-002-0946-y] [Citation(s) in RCA: 172] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2002] [Revised: 05/29/2002] [Indexed: 12/12/2022]
Abstract
AIMS/HYPOTHESIS Proteinuria, reflecting increased glomerular permeability to macromolecules is a characteristic feature of diabetic nephropathy. Nephrin, a 1241-residue transmembrane protein is a key component of the podocyte slit pore membrane and a major contributor of the glomerular filtration barrier. We investigated the expression of nephrin in human kidney tissue from patients with diabetic nephropathy to elucidate its relationship with proteinuria and the effects of anti-proteinuric therapy with angiotensin converting enzyme inhibition. METHODS Renal biopsies were examined from 14 patients with Type II (non-insulin-dependent) diabetes mellitus and proteinuria who had been randomised to receive treatment with the ACE inhibitor, perindopril (4 mg/day) or placebo for the preceding 2 years. These specimens were compared with control human tissue sections, obtained from areas of normal renal cortex following nephrectomy for malignancy. Proteinuria was measured, specimens were examined histologically for injury and the expression of nephrin messenger RNA was assessed by quantitative in situ hybridisation. RESULTS Glomeruli from placebo-treated patients with diabetic nephropathy, showed a 62% reduction in nephrin expression compared with control subjects (p=0.0003). In contrast, nephrin RNA in glomeruli from perindopril treated patients was similar to that in the non-diabetic control group. In both placebo and perindopril treated patients, a close inverse correlation was noted between the magnitude of nephrin gene expression and the degree of proteinuria (placebo: r=0.86, p=0.013, perindopril: r=0.91, p=0.004). CONCLUSION/INTERPRETATION Modulation in nephrin expression is related to the extent of proteinuria in diabetic nephropathy. These changes define, at a molecular level alterations in the glomerulus that occur in relation to proteinuria in diabetes and the effects of anti-proteinuric treatment with ACE inhibition.
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Affiliation(s)
- R G Langham
- University of Melbourne Department of Medicine, St. Vincent's Hospital, Fitzroy, Victoria, Australia
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31
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Langham RG, Egan MK, Dowling JP, Gilbert RE, Thomson NM. Transforming growth factor-beta1 and tumor growth factor-beta-inducible gene-H3 in nonrenal transplant cyclosporine nephropathy. Transplantation 2001; 72:1826-9. [PMID: 11740395 DOI: 10.1097/00007890-200112150-00019] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cyclosporine nephropathy (CyAN) is a major limiting factor in the otherwise successful widespread use of cyclosporine in solid organ transplant. Transforming growth factor-beta1 (TGF-beta1) has been implicated as an important fibrogenic cytokine in the development of this disease. TGF-beta-inducible gene-H3 (beta(ig)-H3) is a TGF-beta1- induced gene product, which acts as a marker for biologically active TGF-beta1. This study reports TGF-beta1 gene expression and beta(ig)-H3 tissue distribution in non-renal allograft CyAN. Renal tissue from nine patients who had developed CyAN after successful heart or heart-lung transplantation and from four kidneys removed for tumour were analyzed for TGF-beta1 gene expression beta(ig)-H3 protein with reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. TGF-beta1 gene expression was increased in CyAN compared to nephrectomy (P<0.0001). Beta(ig)-H3 protein expression was identified in distal convoluted tubular epithelium and parietal glomerular epithelium in CyAN, and not in nephrectomy samples. Expression of TGF-beta1 mRNA was significantly higher in renal tissue from patients not receiving angiotensin converting enzyme inhibitor (ACEI) therapy for hypertension (P<0.05). These findings support the hypothesis that TGF-beta1 is an important cytokine in the development of CyAN, independent of its role in chronic rejection in renal allografts.
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Affiliation(s)
- R G Langham
- Monash University, Department of Medicine, Prahran, Melbourne, VIC, Australia 3181
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32
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Peterson LA, Thomson NM, Crankshaw DL, Donaldson EE, Kenney PJ. Interactions between methylating and pyridyloxobutylating agents in A/J mouse lungs: implications for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced lung tumorigenesis. Cancer Res 2001; 61:5757-63. [PMID: 11479212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The tobacco-specific nitrosamine, 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone, is activated to lung DNA methylating and pyridyloxobutylating intermediates. It is likely that both pathways play a role in lung tumor initiation by this nitrosamine. Previous studies indicated that O(6)-methylguanine (O(6)-mG) persistence is critical for lung tumor formation in A/J mice. The model pyridyloxobutylating agent, 4-(acetoxymethylnitrosamino)-1-(3-pyridyl)-1-butanone (NNKOAc), enhanced the tumorigenic activity of a model methylating agent, acetoxymethylmethylnitrosamine (AMMN), presumably by increasing O(6)-mG persistence in lung DNA. We have been testing the hypothesis that the pyridyloxobutylation pathway increases the mutagenic activity of the DNA methylation pathway by preventing the repair of O(6)-mG by O(6)-alkylguanine-DNA alkyltransferase (AGT). In this study, we report that NNKOAc depletes AGT in lungs but not livers of A/J mice. The consequences of AGT depletion by NNKOAc were then compared with those observed with a known AGT inhibitor, O(6)-benzylguanine (O(6)-bG). NNKOAc and O(6)-bG had similar effects on the levels of AMMN-derived O(6)-mG at 4 and 96 h postinjection. This increase in O(6)-mG levels correlated to increased lung tumor multiplicity in animals simultaneously treated with AMMN (0.75 or 1 micromol) and NNKOAc or O(6)-bG. Only NNKOAc significantly increased lung tumor multiplicity at doses of 0.25 or 0.5 micromol AMMN. The results from these studies indicate that the pyridyloxobutylating agent, NNKOAc, can influence the tumorigenic activity of methylating agents in two ways. At low AMMN doses, the increase in tumor multiplicity is dominated by the additive tumorigenic properties of AMMN and NNKOAc. At higher AMMN doses, NNKOAc appears to enhance the tumorigenic activity of AMMN through enhanced depletion of the repair protein, AGT, leading to increased O(6)-mG persistence. It is likely that similar interactions are important for the organospecific effects of 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone.
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Affiliation(s)
- L A Peterson
- Division of Environmental and Occupational Health and Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA.
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33
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de Bruin RW, Stein-Oakley AN, Kouwenhoven EA, Maguire JA, Jablonski P, Jin XJ, Dowling J, Thomson NM. Functional, histological, and inflammatory changes in chronically rejecting small bowel transplants. Transpl Int 2000; 13:1-11. [PMID: 10743683 DOI: 10.1007/s001470050001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Our aim was to develop a model of chronic rejection (CR) in small bowel allografts, and to study the changes occurring in these grafts. Small bowel transplantation was performed using the DA to AS rat strain combination. Short-term (5 mg/kg intramuscular, from days -2 to +9), or long-term cyclosporin treatment (5 mg/kg, 3 times a week until day 50) was given to prevent acute rejection. Controls were untreated allografts, DA isografts with and without cyclosporin, and normal DA and AS rats. They were followed for 50 and 100 days after transplantation. Recipients of a syngeneic graft lost weight during the first week after transplantation, but started to regain weight and kept growing thereafter. Histology showed normal bowel architecture with normal mesenteric lymph nodes and Peyers patches. Vigorous acute rejection occurred in the untreated allografts. Animals had persistent weight loss, and were killed between 6-13 days after transplantation. No clinical signs of graft-versus-host disease were seen. Histology showed end-stage acute rejection. In both cyclosporin-treated allografted groups the postoperative course was as in the isografted animals. However, all animals had histologic signs of CR by 50 and 100 days after transplantation. Changes were most prominent in the mesentery. Serositis with increased vascularity, inflammation with sclerosis, and patchy myointimal proliferation with endothelialitis of the mesenteric vessels were found. Changes in the bowel were patchy and included some thickening of the muscle coat, crypt hyperplasia, scattered necrotic cells in the crypts, slight blunting of villi and loss of goblet cells. Infiltrating cells in the mesentery and bowel consisted mainly of CD 4+ cells, CD 8- T-cells and monocytes/macrophages. Lactulose-mannitol urinary excretion ratio was significantly increased in short-term cyclosporin treated allografts at days 50 and 100 posttransplant. Serum albumin levels were significantly lowered in this group at both time points examined. We developed two models in which CR occurs after small bowel transplantation. Long-term cyclosporin treatment delayed the development of CR, since functional abnormalities were only seen in the animals that were treated with short-term cyclosporin.
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Affiliation(s)
- R W de Bruin
- Erasmus University, Laboratory for Experimental Surgery, Rotterdam, The Netherlands
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Chin KC, Perry GJ, Dowling JP, Thomson NM. Primary T-cell-rich B-cell lymphoma in the kidney presenting with acute renal failure and a second malignancy. Pathology 1999; 31:325-7. [PMID: 10643001 DOI: 10.1080/003130299104675] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Infiltration of the kidney is commonly found in lymphoma, but acute renal failure arising from bilateral renal infiltration is uncommon. Primary renal lymphoma may occur and is usually of B-cell lineage. It is rare for patients with lymphoma to develop acute renal failure as their initial clinical presentation. Recently, an association between primary renal lymphoma and a second primary malignancy has been reported. We describe the first case of a renal T-cell-rich B-cell lymphoma presenting as acute renal failure, which was associated with a second primary pulmonary malignancy.
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Affiliation(s)
- K C Chin
- Department of Renal Medicine, Alfred Hospital, Melbourne, Australia
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35
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Affiliation(s)
- S A Menahem
- Department of Renal Medicine, Alfred Hospital, Melbourne, Australia
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36
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Abstract
Long-term survival of small bowel transplants is hampered by chronic rejection. Epidermal growth factor (EGF) and transforming growth factor beta (TGF-beta) have opposing, regulatory roles in normal intestinal physiology and may be involved in the pathogenesis of chronic intestinal rejection. Our aim was to investigate the expression of EGF and TGF-beta1 in chronically rejecting small bowel transplants. Orthotopic small bowel transplantation was performed in the allogeneic DA-to-AS rat combination; Cyclosporin was administered temporarily to prevent acute rejection. Controls were DA isografts and normal DA rats. PreproEGF and TGF-beta1 gene expression was evaluated by northern blot analysis of the ileum RNA and standardized against glyceraldehyde-3-phosphate-dehydrogenase expression. Allografts demonstrated functional impairment and histological features of chronic rejection, whereas isografts appeared normal. Allografts demonstrated a significant reduction of EGF mRNA when compared to DA isografts. No significant changes were detected in TGF-beta1 expression in either allogeneic or syngeneic grafts. In conclusion, this study demonstrates reduced preproEGF and preserved TGF-beta1 gene expression in chronically rejecting small bowel transplants.
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MESH Headings
- Analysis of Variance
- Animals
- Blotting, Northern/methods
- Blotting, Northern/statistics & numerical data
- Chronic Disease
- Disease Models, Animal
- Epidermal Growth Factor/analysis
- Epidermal Growth Factor/physiology
- Gene Expression Regulation/physiology
- Graft Rejection/genetics
- Graft Rejection/pathology
- Graft Rejection/physiopathology
- Intestine, Small/chemistry
- Intestine, Small/pathology
- Intestine, Small/physiopathology
- Intestine, Small/transplantation
- Male
- RNA, Messenger/analysis
- Rats
- Rats, Inbred Strains
- Statistics, Nonparametric
- Transforming Growth Factor beta/analysis
- Transforming Growth Factor beta/physiology
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Affiliation(s)
- E A Kouwenhoven
- Department of Medicine, Monash Medical School, Melbourne, Victoria, Australia
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Kouwenhoven EA, Stein-Oakley AN, Maguire JA, Jablonski P, de Bruin RW, Thomson NM. Increased expression of basic fibroblast growth factor during chronic rejection in intestinal transplants is associated with macrophage infiltrates. Transpl Int 1999; 12:42-9. [PMID: 10080405 DOI: 10.1007/s001470050183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Long-term survival of intestinal transplants is hampered by chronic rejection (CR). Since transplants with CR demonstrate fibrotic changes, the cytokine basic fibroblast growth factor (bFGF) may be involved in the tissue remodelling of chronic intestinal rejection. The aim of this study was to investigate the bFGF gene and protein expression and distribution in chronically rejecting intestinal allografts. Orthotopic small bowel transplantation was performed in the allogeneic DA-to-AS rat combination. Cyclosporin was administered temporarily to prevent acute rejection. Controls were DA isografts and normal DA. bFGF gene expression was evaluated using reverse transcriptase polymerase chain reaction (RT-PCR) of the ileum RNA and was standardized against Glyceraldehyde-3-phosphate-dehydrogenase (GAP-DH) expression. bFGF protein was determined using immunohistochemistry. To identify the bFGF-positive cell type, sequential sections were stained for cell markers. Allografts showed histological features of CR, whereas isografts preserved normal architecture. bFGF gene expression was present in normal ileum and significantly upregulated in allografts. Immunohistochemical staining showed a significant increase in bFGF protein compared to isografts. Most bFGF-positive cells were localized in the submucosa and muscularis, particularly around the neural plexus. bFGF-positive cells appeared to be ED-2-positive macrophages, strongly suggesting that the site of bFGF production is the activated macrophage. This study demonstrates increased bFGF mRNA and protein in chronically rejecting intestinal allografts that appear to be produced by macrophages.
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Affiliation(s)
- E A Kouwenhoven
- Department of Medicine, Monash Medical School, Monash University, Melbourne, Victoria, Australia.
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Bombas A, Stein-Oakley AN, Baxter K, Thomson NM, Jablonski P. Development of injury in a rat model of chronic renal allograft rejection: effect of dietary protein restriction. Transpl Int 1999; 12:18-26. [PMID: 10080402 DOI: 10.1007/s001470050180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Non-allogeneic factors such as increased nephron "workload" may contribute to chronic renal allograft rejection. Reducing dietary protein from 20% to 8% was tested in a model of chronic rejection: Dark Agouti kidney to Albino Surgery recipient, "tolerised" by previous donor blood transfusions. Survival, weight gain, serum creatinine concentration and creatinine clearance were similar for both groups at all times. Urinary protein was significantly (P < 0.05) lower in the low-protein (LP) group 1 month after transplantation. After 3 and 6 months, both groups demonstrated mild chronic rejection. After 6 months, tubular atrophy was significantly (P < 0.05) less in the LP group and interstitial fibrosis was marginally reduced. Glomerular hypertrophy, glomerular sclerosis, tubular dilatation, leucocyte infiltration, adhesion molecule expression and TGF-beta1 mRNA expression were similarly increased in both groups. Thus, reducing dietary protein to 8% lowered urinary protein, but did not significantly affect the development of chronic rejection in renal allografts beyond affording a degree of protection from tubulointerstitial damage.
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Affiliation(s)
- A Bombas
- Department of Medicine, Monash Medical School, Alfred Hospital, Prahran, Victoria, Australia.
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Egan MK, Langham RG, Richardson M, Bergin P, Kaye D, Bailey M, Dowling J, Thomson NM, Stein-Oakley AN. Quantitative analysis of PDGFA, PDGFB, PDGF receptor beta and TGF-beta 1 mRNA in cardiac transplant biopsies. Transplant Proc 1999; 31:131-2. [PMID: 10083043 DOI: 10.1016/s0041-1345(98)01473-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M K Egan
- Department of Medicine, Monash Medical School, Prahran, Australia
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Kouwenhoven EA, Stein-Oakley AN, Maguire JA, Jablonski P, de Bruin RW, Thomson NM. Upregulation of basic fibroblast growth factor during chronic intestinal rejection. Transplant Proc 1999; 31:590. [PMID: 10083250 DOI: 10.1016/s0041-1345(98)01570-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- E A Kouwenhoven
- Department of Medicine, Monash University, Melbourne, Australia
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Bakharevski O, Stein-Oakley AN, Thomson NM, Ryan PF. Collagen induced arthritis in rats. Contrasting effect of subcutaneous versus intradermal inoculation of type II collagen. J Rheumatol 1998; 25:1945-52. [PMID: 9779848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
OBJECTIVE To determine the effect of subcutaneous (s.c.) as compared to intradermal (i.d.) inoculation of collagen type II (CII) in induction of collagen induced arthritis (CIA). METHODS Dark Agouti (DA) and Lewis rats were injected with CII either i.d. or s.c.. A group of s.c. inoculated DA rats was re-injected with CII intradermally 45 days after first injection (s.c./i.d.). Arthritis was assessed by macroscopic scoring, histology, and immunohistochemistry. Levels of anti-CII antibody subtypes were measured by ELISA. RESULTS Intradermal but not s.c. inoculation of CII resulted in histologically confirmed erosive arthritis in both Lewis and DA strains. Subcutaneous/intradermal inoculated DA rats developed mild CIA with lower arthritic scores and delayed onset. Lewis rats injected s.c. had lower levels of total Ig, IgG, IgG2a, and IgG2b and similar titers of IgG1 compared to i.d. inoculated rats. In contrast, only IgG2b levels were lower in s.c./i.d. compared to i.d. rats. CONCLUSION Our data suggest that s.c. administration of CII tolerises animals against autoimmune CIA.
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Affiliation(s)
- O Bakharevski
- Department of Medicine, Monash Medical School, Alfred Hospital, Prahran, Victoria, Australia.
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Hitchcock SA, Houldsworth SJ, Pattenden G, Pryde DC, Thomson NM, Blake AJ. A tandem radical macrocyclisation-transannular cyclisation approach towards the taxanes. ACTA ACUST UNITED AC 1998. [DOI: 10.1039/a805268i] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Houldsworth SJ, Pattenden G, Pryde DC, Thomson NM. Studies towards the taxane ring system via a cascade macrocyclisation–transannulation strategy. ACTA ACUST UNITED AC 1997. [DOI: 10.1039/a700784a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Jablonski P, Baxter K, Howden BO, Marshall VC, Stein-Oakley A, Thomson NM. The effect of ureteric stenting on the function and morphology of long-term rat renal allografts. Aust N Z J Surg 1995; 65:499-502. [PMID: 7611971 DOI: 10.1111/j.1445-2197.1995.tb01794.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
In the development of a reliable model for chronic rejection in rat renal allografts, the effect of modifying the ureteric anastomosis was tested. Rats, tolerized by pretreatment with two donor blood transfusions under Cyclosporin A, received renal allografts with either sewn or stented ureter. Control groups received isografts or underwent uninephrectomy with insertion of ureteric stents. For the first 6 days after transplantation, serum creatinine and urea values were lower in allograft recipients with stented ureters than in the group with sewn ureters. The method of ureteric anastomosis did not affect the long-term incidence of abnormal function. Allograft morphology was extremely variable from minor to extensive tubular atrophy, interstitial fibrosis, glomerular hypertrophy, focal and segmental glomerulosclerosis as well as vascular changes. Glomerulosclerosis was absent in controls and increased with time in the allografts. Two hundred days after transplantation all allograft recipients with sewn ureters exhibited some glomerulosclerosis, in half of these kidneys more than 25% of glomeruli were affected. Only 33% recipients of allografts with stented ureters exhibited some glomerulosclerosis and less than 20% of glomeruli were affected. The stented ureteric anastomosis provides a reliable method, a reduction of the technical failure rate, a reduction of the incidence of hydronephrosis, allows more accurate assessment of early renal function and may be of importance in reducing the occurrence and prevalence of glomerulosclerosis in the long-term allografts.
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Affiliation(s)
- P Jablonski
- Monash University Department of Surgery, Monash Medical Centre, Clayton, Victoria, Australia
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Abstract
The high rates of drug-induced acute renal failure, worsening chronic renal dysfunction and systemic toxicity of renally excreted drugs in the elderly can be minimised by carefully assessing renal function, avoiding potentially nephrotoxic drugs as much as possible and closely monitoring drug concentrations and renal function when they must be used. The co-existence of impaired renal function, degenerative vascular disease or cardiac failure in the elderly substantially increases the risk of renal toxicity. When in doubt about potential nephrotoxicity or an increased risk of systemic toxicity from renally excreted drugs in the elderly, the practitioner should consult the numerous published guidelines.
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Affiliation(s)
- N M Thomson
- Department of Medicine, Monash Medical School, Alfred Hospital, Alfred HealthCare Group, Melbourne, VIC
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Jablonski P, Baxter K, Howden BO, Thomas AC, Marshall VC, Stein-Oakley A, Thomson NM. A reproducible model of chronic rejection in rat renal allografts. Aust N Z J Surg 1995; 65:114-9. [PMID: 7857223 DOI: 10.1111/j.1445-2197.1995.tb07274.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A reproducible animal model is essential for the study of the pathogenesis of chronic rejection. This study investigates: (i) the optimal pre-transplant blood transfusion conditions to induce tolerance in a strongly rejecting rat kidney allograft model (Dark Agouti to Albino-Surgery) and avoiding post-transplant immunosuppression; (ii) the functional and histological changes that occur in long-term surviving kidneys and their similarity to chronic rejection; and (iii) the maintenance of tolerance. Prolonged survival occurred after administration of at least two donor blood transfusions with concomitant cyclosporin A (5 mg/kg per day). The time-span between transfusions appeared to be critical: 4 days was more effective than 2 or 7 days. Ineffective treatment led to death within the first 2 weeks post-transplant with histological evidence of acute graft rejection. Seventy-five per cent of long-term survivors experienced impaired renal function in the first week which improved spontaneously and remained stable in 93% of the surviving animals after 100 days and in 66% after 200 days. The morphology of long-term allografts was extremely variable from minor to extensive tubular atrophy, interstitial fibrosis, glomerular hypertrophy, focal and segmental glomerulosclerosis and vascular changes. Glomerular hypertrophy occurred in uninephrectomized controls and probably denoted a response to uninephrectomy. Glomerulosclerosis increased with time and was absent in controls. Although chronic damage was evident, the rats remained tolerant to fresh donor skin. Replacement of the original kidney allograft with a fresh donor kidney resulted in 70% survival. These second grafts showed less severe renal dysfunction and morphological damage than the original allografts in the long-term follow up.
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Affiliation(s)
- P Jablonski
- Monash University Department of Surgery, Monash Medical Centre, Clayton, Victoria, Australia
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Stein-Oakley AN, Tzanidis A, Fuller PJ, Jablonski P, Thomson NM. Expression and distribution of epidermal growth factor in acute and chronic renal allograft rejection. Kidney Int 1994; 46:1207-15. [PMID: 7861718 DOI: 10.1038/ki.1994.386] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Epidermal growth factor (EGF) is a fibrogenic cytokine with a possible role in chronic damage. EGF is also involved in tubular regenerative response to injury. This study investigates the expression and distribution of EGF in a rat model of renal allograft rejection. EGF was localised in control kidneys to distal convoluted tubules (DCT) and thick ascending loop of Henle (TAL). Five days post-transplantation EGF was diffusely distributed. In chronic rejection at one, three and six months, damaged areas of allografts demonstrated faint diffuse EGF staining, while well-preserved areas exhibited the normal distribution pattern. PreproEGF mRNA was significantly reduced (P < 0.01) in acute rejection and in chronic rejection at three months to 28% and 51% of normal, respectively. At six months values ranged from 16% to 166% of normal kidneys, and were inversely correlated with tubular damage (P < 0.01). PreproEGF mRNA was localized to DCT and TAL in controls and in well preserved areas of the tissue in chronic rejection. Thus, EGF would not appear to contribute to the development of injury in chronic renal rejection. It may instead exert a protective effect on tubular structures.
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Affiliation(s)
- A N Stein-Oakley
- Department of Medicine, Monash Medical School, Monash University, Victoria, Australia
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Stein-Oakley AN, Jablonski P, Tzanidis A, Baxter K, Howden BO, Marshall VC, Thomson NM. Development of chronic injury and nature of interstitial infiltrate in a model of chronic renal allograft rejection. Transplantation 1993; 56:1299-305. [PMID: 8278992 DOI: 10.1097/00007890-199312000-00002] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A model of chronic renal rejection in the Dark-Agouti to Albino-Surgery rat combination is described. In a number of cases, the original allograft was replaced by a second Dark-Agouti allograft. Seventy-five percent of rats experienced early episodes of rejection that subsided spontaneously. Second allografts had better initial renal function. Variable degrees of tubular atrophy, interstitial fibrosis, vascular damage, glomerulosclerosis, deposition of humoral mediators, and mononuclear leukocyte infiltrate were observed in all long-term allografts. Chronic damage increased with time, and was less severe in second allografts. At 5 days, total interstitial infiltrate was similar to that seen in unmodified rejection, but there was a significant increase in CD4+ cells and a decrease in ED2 and IL-2R expression. Subsequently, the total interstitial infiltrate decreased with time, although it remained significantly higher than in isografts and residual kidneys from uninephrectomized rats. No significant decrease over time was seen in numbers of CD4+ and CD45RC+ cells. The latter had a marked focal distribution after 100 days. Total leukocyte infiltrate was similar in original and second allografts, but there were changes in the proportions of leukocyte subpopulations, including significantly lower numbers of CD45RC+ cells in the latter. The persistence of CD45RC+ cells throughout the course of chronic rejection and their lower numbers in the second allografts favors a role for these cells in the development of chronic injury. The model of chronic renal allograft rejection characterized in this study will be valuable in further studies of the mechanisms of injury in this pathology.
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Affiliation(s)
- A N Stein-Oakley
- Department of Medicine, Monash Medical School, Alfred Hospital, Prahran, Australia
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Stein-Oakley AN, Tzanidis A, Fuller PJ, Jablonski P, Thomson NM. Chronic renal allograft rejection: altered distribution and reduced expression of epidermal growth factor in a rat model. Transplant Proc 1993; 25:2902-3. [PMID: 8212280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- A N Stein-Oakley
- Monash Department of Medicine, Alfred Hospital, Prahran, Victoria, Australia
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Thomson NM, Scully G, Knudson R, Wragg F, Keaney L, Angus J, White G, Marshall A. Transplantation--the issues: a cross curriculum programme for secondary schools. Transplant Proc 1993; 25:1687-9. [PMID: 8442237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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