Linking genotypic variation of Salmonella Typhimurium

Lead Research Organisation: University of East Anglia
Department Name: Biological Sciences

Abstract

Salmonellosis is a foodborne infectious disease which has a significant impact on the health of humans, and both wild and domesticated animals. Bacteria are constantly under attack from bacterial viruses called bacteriophage (phage), an interaction with consequences on evolution but that is also exploitable for diagnostics and therapy. This project will investigate the variation in phage resistance mechanisms of Salmonella Typhimurium that will contribute to the understanding of the biology of an important food borne pathogen and to development of surveillance diagnostics and phage therapy. An understanding of the mechanisms underlying phage exclusion is relevant to i) define the molecular basis of phage typing in surveillance ii), understand of how pathogens evolve, and iii) provide underpinning knowledge relevant to phage therapy.

Publications

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Studentship Projects

Project Reference Relationship Related To Start End Student Name
BB/M011216/1 01/10/2015 30/09/2023
1762955 Studentship BB/M011216/1 01/04/2016 23/03/2021 Oliver Charity
 
Description There are two main areas:

1. I have helped describe and characterise a new class of genomic Island in important human pathogen: Salmonella genomic Island 4 (SGI-4) and its group of elements SGI-4 like elements (SLE) where the former is present in emerging monophasic Salmonella enterica serovar Typhimurium, and the latter present in various species of Enterobacteriacae. It was discovered that acquisition of this element was consistent with a clonal expansion of a now global pandemic, likely through enhanced copper resistance and homeostasis. Experimentation has shown that the element was transferable to other Salmonella and Escherichia coli. Transfer was increased with oxygen tension and DNA intercalation agent mitomycin c. PCR based assays have shown that the element was successfully transfered, in the same position, and formed an intermittant circular version prior to transfer. This is currently in an accepted publication, although still under review.

2. The second part has been describing genetic polymorphisms associated with differences in phage resistance of current emerging Salmonella Typhimurium, one set associated with an epidemic in ducks and humans and the other with the previously described pandemic Monophasic Salmonella Typhimurium. Here specific polymorphisms have been associated with different phage resistance profiles using bacterial genome wide association. This is ongoing work which will almost certainly end in publication.
Exploitation Route 1. Increasing the knowledge of how pathogens become successful in the food production process, in this case increased heavy metal resistance, will inform policy makers and farmers alike as to how we can prevent the expansion of deadly human pathogenic clones of bacteria.

2. Informing scientists and pathogen therapy companies on how bacteria such as Salmonella develop resistance in short timescales will influence the use of bacteriophage on farms and hospitals, as well as potentially modify current trends of changing animal husbandry throughout the world.
Sectors Agriculture, Food and Drink,Chemicals,Digital/Communication/Information Technologies (including Software),Education,Environment,Healthcare,Manufacturing, including Industrial Biotechology,Pharmaceuticals and Medical Biotechnology