Microbiology

eLife Assessment

These authors present findings on the role of the sirtuins SIRT1 and SIRT3 during Salmonella Typhimurium infection. This valuable study increases our understanding of the mechanisms used by this pathogen to interact with its host and may have implications for other intracellular pathogens. The reviewers disagreed on the strength of the evidence to support the claims. Although one reviewer found the strength of the evidence convincing, the other found that it was incomplete, and that the main claims are only partially supported, as can be seen from the public reviews.

eLife Assessment

This important study examines the role of Microrchidia (MORC) proteins in the human malaria parasite Plasmodium falciparum. Solid experimental results, including genome editing and chromatin profiling methods (ChIP-seq and Hi-C), provide a comprehensive picture of the critical role MORC plays in shaping parasite chromatin. Depletion of MORC results in a lethal collapse of heterochromatin and parasite death, nominating the factor as a new target of antimalarial therapies.

eLife Assessment

This valuable study describes how a single effector of the Type Six Secretion System (T6SS) has two distinct enzymatic functions that together may contribute to bacterial survival and dynamics in a community and provide potential for developing new antimicrobial compounds. The authors have deployed a range of methods in biochemistry, microbiology, and microscopy, generating solid data that support the main assertions. While the manuscript could benefit from additional clarifying experiments and a more detailed discussion of the methods, it will appeal to those studying T6SS, particularly those interested in effectors and bacterial enzymes.

eLife Assessment

This study by Graca et al. explores ethanol metabolism pathways in mycobacteria. The enzyme, MftG, a flavoprotein dehydrogenase, is shown to act as an electron shuttle between an uncommon redox cofactor and the electron transport chain thereby regenerating mycofactocin. Whilst this study was conducted in Mycobacterium smegmatis, the findings are important and have general implications for elucidating broader mycobacterial metabolism. Overall, the data presented are convincing supported by well-designed experiments.

eLife Assessment

In this important study, the authors set out to investigate the biogenesis of extracellular vesicles in mycobacteria and provide several observations to link VirR with vesiculogenesis, PG metabolism, lipid metabolism, and cell wall permeability. Whilst some of the evidence provided is convincing, there are still some shortcomings in the revised manuscript where the data to support the proposed mechanism remain incomplete. The work will be of interest to bacteriologists.

eLife Assessment

In this useful study, Wang and colleagues investigate the potential probiotic effects of Bacillus velezensis in a murine model. They provide convincing evidence that B. velezensis limits the growth of Salmonella typhimurium in lab culture and in mice, together with beneficial effects on the microbiota. The overall presentation of the manuscript has improved and the work will be of interest to infectious disease researchers.

eLife Assessment

This important study shows that Toxoplasma gondii uses paracrine mechanisms, in addition to cell-intrinsic methods, to evade the host immune system, with MYR1 playing a key role in transporting effector molecules into host cells. The authors present convincing evidence that in vivo, MYR1-deficient parasites can be rescued by wild-type parasites, revealing a limitation in pooled CRISPR screens, where such paracrine effects may obscure the identification of key parasite pathways involved in immune evasion.

eLife Assessment

This important study reports a detailed quantification of the population dynamics of Salmonella enterica serovar Typhimurium in mice. Bacterial burden and founding population sizes across various organs were quantified, revealing pathways of dissemination and reseeding of the gastrointestinal tract from systemic organs. Using various techniques, including genetic distance measurements, the authors present compelling evidence to support their conclusions, thus presenting new knowledge that will be of broad interest to scientists focusing on infectious diseases.

eLife Assessment

This important study uses a large dataset from both recent isolates and genomes in databases to provide an analysis of the population structure of the pathogen Salmonella gallinarum. The results regarding regional adaptation and the evolutionary trajectory of the resistome and mobilome remain incomplete, requiring additional details to fully support their claims and assess the value of these insights for future policy interventions regarding this and other pathogens. This work will interest microbiologists and researchers working on genomics, evolution, and antimicrobial resistance.

eLife Assessment

This valuable report describes the changing antiviral activity of IFIT1 across mammals and in response to distinct viruses, likely as a result of past arms races. One of the main strengths of the manuscript is the breadth of mammalian IFIT1 orthologs and viruses that were tested. Overall the evidence is solid, but the analysis of positive selection could benefit from more thorough validation with complementary selection tests and also from assessing or more extended discussion of the impact of recombination and/or physical interactions with other IFITs.