Evidence map›Paper›PMID 35780105›Full record

ArticleMicrobial cell factories2022

Enhanced protein translocation to mammalian cells by expression of EtgA transglycosylase in a synthetic injector E. coli strain.

Beatriz Álvarez, Víctor Muñoz-Abad, Alejandro Asensio-Calavia, Luis Ángel Fernández

Abstract read
In one paragraph

Article in Microbial cell factories, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

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5 · Who and what money

Authors and funding

4 authors.

Beatriz ÁlvarezDepartment of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, Campus Cantoblanco, 28049, Madrid, Spain.ORCID http://orcid.org/0000-0002-9613-5473
Víctor Muñoz-AbadDepartment of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, Campus Cantoblanco, 28049, Madrid, Spain.ORCID http://orcid.org/0000-0001-6447-8212
Alejandro Asensio-CalaviaDepartment of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, Campus Cantoblanco, 28049, Madrid, Spain.ORCID http://orcid.org/0000-0001-8113-6599
Luis Ángel FernándezDepartment of Microbial Biotechnology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CNB-CSIC), Darwin 3, Campus Cantoblanco, 28049, Madrid, Spain. lafdez@cnb.csic.es.ORCID http://orcid.org/0000-0001-5920-0638

Funding

H2020 Excellent Science FET Open 965018-BIOCELLPHEMinisterio de Ciencia e Innovación BIO2017-89081-R
6 · The paper itself

Abstract

backgroundBacterial type III secretion systems (T3SSs) assemble a multiprotein complex termed the injectisome, which acts as a molecular syringe for translocation of specific effector proteins into the cytoplasm of host cells. The use of injectisomes for delivery of therapeutic proteins into mammalian cells is attractive for biomedical applications. With that aim, we previously generated a non-pathogenic Escherichia coli strain, called Synthetic Injector E. coli (SIEC), which assembles functional injectisomes from enteropathogenic E. coli (EPEC). The assembly of injectisomes in EPEC is assisted by the lytic transglycosylase EtgA, which degrades the peptidoglycan layer. As SIEC lacks EtgA, we investigated whether expression of this transglycosylase enhances the protein translocation capacity of the engineered bacterium.

resultsThe etgA gene from EPEC was integrated into the SIEC chromosome under the control of the inducible tac promoter, generating the strain SIEC-eEtgA. The controlled expression of EtgA had no effect on the growth or viability of bacteria. Upon induction, injectisome assembly was ~ 30% greater in SIEC-eEtgA than in the parental strain, as determined by the level of T3SS translocon proteins, the hemolytic activity of the bacterial strain, and the impairment in flagellar motility. The functionality of SIEC-eEtgA injectisomes was evaluated in a derivative strain carrying a synthetic operon (eLEE5), which was capable of delivering Tir effector protein into the cytoplasm of HeLa cells triggering F-actin polymerization beneath the attached bacterium. Lastly, using β-lactamase as a reporter of T3SS-protein injection, we determined that the protein translocation capacity was ~ 65% higher in the SIEC-EtgA strain than in the parental SIEC strain.

conclusionsWe demonstrate that EtgA enhances the assembly of functional injectisomes in a synthetic injector E. coli strain, enabling the translocation of greater amounts of proteins into the cytoplasm of mammalian cells. Accordingly, EtgA expression may boost the protein translocation of SIEC strains programmed as living biotherapeutics.

Indexed as

Cell EngineeringEnteropathogenic Escherichia coliEscherichia coli ProteinsGlycosyltransferasesHeLa CellsHumansProtein TransportEscherichia coli ProteinsGlycosyltransferasesE. coliEtgAInjectisomesPeptidoglycanProtein translocationSIECType III secretion systems

Identifiers

PMID35780105
PMCPMC9250224

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.