Microbiology

Bacteria detect neutrophils via a system that responds to hypochlorous acid and flow

1. Ilona P. Foik
2. Summer J. Kasallis
3. Runhang Shu
4. Serena Abbondante
5. Michaela E. Marshall
6. Lauren A. Urban
7. Leora Duong
8. Andy P. Huang
9. Eric Pearlman
10. Timothy L. Downing
11. Albert Siryaporn

• Curated by eLife

  eLife Assessment

  This is an important study reporting a new phenotype for a gene cluster that has previously been associated with the responses of the Gram-negative opportunistic pathogen Pseudomonas aeruginosa to flow fluid. Expression of the froABCD gene cluster is induced by HOCl in vitro and by activated immune cells, which produce these types of reactive chlorine species and the evidence presented by the authors is in many places convincing. Overall, the authors have been responsive to the previous review, although the exact mechanism of fro-induction by HOCl remains unclear. The high cysteine- and methionine content of the anti-sigma factor FroI hints at a direct oxidative modification of this protein during activation of the operon and a corneal infection model shows that fro is upregulated in P. aeruginosa 20 h after infection, but the evidence that HOCl is the causative agent of fro upregulation under these conditions is at present circumstantial. This study is of interest to infection biologists interested in mechanisms of bacterial pathogenicity.

Reviewed by eLife

Three metabolic pathways replenishing the one-carbon pool collectively support growth and virulence of Listeria monocytogenes

1. Sandra Freier
2. Sarah Frentzel
3. Moritz Müller
4. Susan Scheffler
5. Sabrina Wamp
6. Tim Engelgeh
7. Janina Döhling
8. Dunja Bruder
9. Sascha Kahlfuss
10. Sven Halbedel

• Curated by eLife

  eLife Assessment

  One-carbon tetrahydrofolate metabolism plays a crucial role in producing essential metabolic intermediates. In this valuable study, the authors employ a solid genetics-based approach to demonstrate that three distinct metabolic pathways are essential for synthesising 1C-tetrahydrofolates (1C-THF). Disrupting any of these pathways impairs both growth and virulence.

Reviewed by eLife

Replicative slender bloodstream forms complete transmission of Trypanosoma brucei without prior differentiation into stumpy forms

1. Carina Praisler
2. Jaime N Lisack
3. Anna Sophie Kreis
4. Laura Hauf
5. Johanna Odenwald
6. Fabian Imdahl
7. Markus Engstler

• Curated by eLife

  eLife Assessment

  The manuscript concerns a fundamental and controversial question in Trypanosoma brucei biology and the parasite life cycle, whether or not dividing slender bloodstream forms must transition to growth-arrested stumpy forms before differentiating to the procyclic form in the Tsetse midgut. The authors provide further evidence that slender bloodstream forms can infect Tsetse flies, and that although their differentiation is considerably delayed, they do not become classical stumpy forms during the process. The study is solid in design and execution, and addresses several criticisms made of the authors' earlier work, although discrepancies with results from other laboratories remain.

Reviewed by eLife

Thermoregulation network governing virulence of a critical human fungal pathogen

1. Vikas Yadav
2. Joseph Heitman

Reviewed by Review Commons

A mitochondrial quality control mechanism reverses the phagosome maturation arrest caused by Mycobacterium tuberculosis

1. Surbhi Verma
2. Shweta Thakur
3. Mrinmoy Das
4. Raman D Sharma
5. Vikas Yadav
6. Priya Sharma
7. Mardiana Marzuki
8. Shihui Foo
9. Giulia M Piperno
10. Mehak Z Khan
11. Babu Mathew
12. Meenu Bajpai
13. Jaswinder Singh Maras
14. Shanshan Howland
15. Sovan Sarkar
16. Federica Benvenuti
17. Amit Singh
18. Vinay Nandicoori
19. Amit Singhal
20. Dhiraj Kumar

• Curated by eLife

  eLife Assessment

  Verma and colleagues interrogate the mechanisms of phagosome maturation arrest during Mycobacterium tuberculosis infection. While cellular events that culminate in this arrest have been largely elucidated, involvement of other organelles, such as mitochondria, has not been highlighted mechanistically. In this valuable study, elements of mitochondrial quality control, such as mitophagy and mitochondrial-derived vesicles involvement, are shown to be paramount in the host-pathogen tussle. The evidence supporting the main conclusions is solid, based on multiple complementary approaches and appropriate controls, although some central mechanistic aspects of the proposed pathway remain only partially resolved.

Reviewed by eLife

High-throughput quantification of population dynamics using luminescence

1. Malte Muetter
2. Daniel C Angst
3. Roland Regoes
4. Sebastian Bonhoeffer

• Curated by eLife

  eLife Assessment

  Muetter et al. provide an important argument that luminescence is a reliable, high-throughput alternative to colony-forming units (CFU) for super-MIC investigations, particularly when the quantity of interest is biomass. By examining 20 antimicrobials spanning 11 classes, the work shows that discrepancies between CFU and luminescence are often biological (filamentation, Viable But Not Culturable). The work provides a convincing view of how these three common measurements (luminescence, optical density, and CFU) relate to one another across a range of drug treatments, although testing on clinical isolates could be of further benefit.

Reviewed by eLife

The vaccine candidate Liver Stage Antigen 3 is exported during Plasmodium falciparum infection and required for liver-stage development

1. Robyn McConville
2. Ryan WJ Steel
3. Matthew T O’Neill
4. Alan F Cowman
5. Norman Kneteman
6. Justin A Boddey

• Curated by eLife

  eLife Assessment

  This useful study provides new insights into the liver-stage antigen LSA3, its export to erythrocytes, and its role in liver-stage development. While the functional importance of LSA3 is well demonstrated, the data underlying the conclusions regarding antibody specificity, liver-stage localization, and phenotype remain incomplete. A key strength of the study is the use of mosquito and humanized mouse models to access life-cycle stages that are rarely studied in most laboratories.

Reviewed by eLife

Nanoscopy reveals heparan sulfate clusters as docking sites for SARS-CoV-2 attachment and entry

1. Sue Han
2. Xin Wang
3. Tiansheng Li
4. Ammar Mohseni
5. Ivan Kosik
6. Chung Yu Chan
7. Alberto Domingo López-Muñoz
8. Jessica Matthias
9. Reid Suddaby
10. Zhixiong Wang
11. Albert J Jin
12. Christian A Wurm
13. Jonathan W Yewdell
14. Ling-Gang Wu

• Curated by eLife

  eLife Assessment

  The authors use solid high resolution microscopy techniques to present a model in which SARS-CoV-2 attachment and endocytosis are mediated by heparan sulfate, whereas ACE2 only functions downstream of these early processes. These findings serve as a potentially valuable starting point to examine SARS-CoV-2 entry models that challenge current paradigms. However, examination of the model in a clean heparan sulfate deficient background and in the context of TMPRSS2-dependent plasma membrane fusion are lacking. Thus, the broader impact remains uncertain in the absence of additional controls and orthogonal approaches.

Reviewed by eLife

Viral commitment to infection depends on host metabolism

1. Anastasios Marantos
2. Kim Sneppen
3. Stanley Brown
4. Namiko Mitarai

• Curated by eLife

  eLife Assessment

  This valuable study shows the impact of the metabolic state of bacteria on phage infection. The experimental results, based on various phages infecting E. coli, are convincing and consistent with a two-step adsorption mathematical model. This study should be of interest to the communities working on cell metabolism and on host-pathogen interactions.

Reviewed by eLife

An abundant merozoite surface protein of Plasmodium falciparum modulates susceptibility to inhibitory antibodies

1. Isabelle G Henshall
2. Jill Chmielewski
3. Dimuthu Angage
4. Ornella Romeo
5. Keng Heng Lai
6. Kaitlin R Turland
7. Nicki Badii
8. Michael Foley
9. Robin F Anders
10. James G Beeson
11. Danny W Wilson

• Curated by eLife

  eLife Assessment

  This important work challenges current models of merozoite surface protein function by showing that MSP2 is dispensable for parasite growth while modulating immune responses to AMA1, with implications for malaria vaccine design. The conclusions are supported by compelling experimental evidence, including state-of-the-art technologies and well-characterized monoclonal antibodies. These findings provide new insights into immune evasion and antigen targeting that will be of broad interest to parasitology, immunology, and vaccine researchers.

Reviewed by eLife