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Type III Secretion Effectors with Arginine N-Glycosyltransferase Activity
Juan Luis Araujo-Garrido1, Joaquín Bernal-Bayard1, Francisco Ramos-Morales1
1Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012 Sevilla, Spain.
Microorganisms
|March 6, 2020
Summary
Gram-negative bacterial pathogens use type III secretion systems to inject effector proteins into host cells. A family of glycosyltransferases, including NleB and SseK, modifies host proteins, impacting NF-κB activation and cell death.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Type III secretion systems (T3SS) are crucial virulence factors in Gram-negative bacterial pathogens.
- T3SS effectors manipulate host cell functions, including signal transduction and cellular processes.
- Glycosylation is an important post-translational modification involved in bacterial pathogenesis.
Purpose of the Study:
- To review a family of bacterial glycosyltransferases that modify host proteins.
- To elucidate the role of these effectors in bacterial virulence and pathogenesis.
- To detail the targets and mechanisms of N-acetyl-d-glucosamine transfer by these effectors.
Main Methods:
- Literature review of T3SS effectors with glycosyltransferase activity.
- Analysis of the glycosyltransferase superfamily and glycosylation in pathogenesis.
- Detailed examination of specific effectors like NleB and SseK and their host targets.
Main Results:
- Identified a family of glycosyltransferases that add N-acetyl-d-glucosamine to arginine residues in host proteins.
- Demonstrated that these modifications reduce NF-κB pathway activation and impair host cell death.
- Highlighted the role of NleB (Citrobacter rodentium), NleB1/NleB2 (E. coli), and SseK1/SseK2/SseK3 (Salmonella enterica) in virulence.
Conclusions:
- Bacterial glycosyltransferases are significant virulence factors that subvert host defenses.
- Targeted modification of host proteins by these effectors provides a novel mechanism for pathogenesis.
- Further research into these effectors can reveal new therapeutic targets for infectious diseases.
Keywords:
CitrobacterEscherichiaNleBSalmonellaSseKdeath domainseffectorsglycosyltransferasestype III secretionMore Related Videos
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