Microreviews, Review
Pirates of the haemoglobin
Daniel Akinbosede1, Robert Chizea1 and Stephen A. Hare1,†
Not all treasure is silver and gold; for pathogenic bacteria, iron is the most precious and the most pillaged of metallic elements. Iron is essential for the survival and growth of all life; however free iron is scarce for bacteria inside human hosts. As a mechanism of defence, humans have evolved ways to store iron so as to render it inaccessible for invading pathogens, such as keeping the metal bound to iron-carrying proteins. For bacteria to survive within humans, they must therefore evolve counters to this defence to compete with these proteins for iron binding, or directly steal iron from them. (...)
An ionophore breaks the multi-drug-resistance of Acinetobacter baumannii
David M.P. De Oliveira1 and Mark J. Walker1
Within intensive care units, multi-drug resistant Acinetobacter baumannii outbreaks are a frequent cause of ventilator-associated pneumonia. During the on-going COVID-19 pandemic, patients who receive ventilator support experience a 2-fold increased risk of mortality when they contract a secondary A. baumannii pulmonary infection. In our recent paper (De Oliveira et al. (2022), Mbio, doi: 10.1128/mbio.03517-21), we demonstrate that the 8-hydroxquinoline ionophore, PBT2 breaks the resistance of A. baumannii to tetracycline class antibiotics. In vitro, the combination of PBT2 and zinc with either tetracycline, doxycycline, or tigecycline was shown to be bactericidal against multi-drug-resistant A. baumannii, (...)
Endomembrane remodeling and dynamics in Salmonella infection
Ziyan Fang1 and Stéphane Méresse1
Salmonellae are bacteria that cause moderate to severe infections in humans, depending on the strain and the immune status of the infected host. These pathogens have the particularity of residing in the cells of the infected host. They are usually found in a vacuolar compartment that the bacteria shape with the help of effector proteins. Following invasion of a eukaryotic cell, the bacterial vacuole undergoes maturation characterized by changes in localization, composition and morphology. In particular, membrane tubules stretching over the microtubule cytoskeleton are formed from the bacterial vacuole. Although these tubules do not occur in all infected cells, they are functionally important and promote intracellular replication. This review focuses on the role and significance of membrane compartment remodeling observed in infected cells and the bacterial and host cell pathways involved.
The small bowel microbiome changes significantly with age and aspects of the ageing process
Gabriela Leite1, Mark Pimentel1,2, Gillian M. Barlow1 and Ruchi Mathur1,3
Gut microbiome changes have been associated with human ageing and implicated in age-related diseases including Alzheimer’s disease and Parkinson’s disease. However, studies to date have used stool samples, which do not represent the entire gut. Although more challenging to access, the small intestine plays critical roles in host metabolism and immune function. In this paper (Leite et al. (2021), Cell Reports, doi: 10.1016/j.celrep.2021.109765), we demonstrate significant differences in the small intestinal microbiome in older subjects, (...)
Lipid and fatty acid metabolism in trypanosomatids
Giovana Parreira de Aquino1,#, Marco Antonio Mendes Gomes1,#, Roberto Köpke Salinas2 and Maria Fernanda Laranjeira-Silva1
This work reviews specific aspects of lipid and fatty acid metabolism in the protozoan parasites T. brucei, T. cruzi, and Leishmania spp., as well as the pathways that have been explored for the development of new chemotherapies.
Understanding the pathogenesis of infectious diseases by single-cell RNA sequencing
Wanqiu Huang1, Danni Wang1 and Yu-Feng Yao1,2
This work highlights recent remarkable advances in single-cell RNA sequencing technologies and their applications in the investigation of host-pathogen interactions. Current challenges and potential prospects for disease treatment are discussed as well.
Exploring absent protein function in yeast: assaying post translational modification and human genetic variation
Christina S. Moesslacher1,#, Johanna M. Kohlmayr1,# and Ulrich Stelzl1,#
This review discusses the applicability of yeast systems to investigate absent human protein function with a specific focus on the impact of protein variation on protein-protein interaction modulation.
LasR-regulated proteases in acute vs. chronic lung infection: a double-edged sword
Lisa C. Hennemann1,2 and Dao Nguyen1,2,3
This article comments on work published by Hennemann et al. (PLoS Pathog, 2021), which observed that in Pseudomonas aeruginosa, functional loss of the quorum sensing transcriptional activator LasR in lasR variants results in impaired secreted protease production, leads to increased expression of the membrane-bound surface adhesion molecule mICAM-1 in the airway epithelium, and increases neutrophilic inflammation.
New insights in the mode of action of anti-leishmanial drugs by using chemical mutagenesis screens coupled to next-generation sequencing
January 21, 2020
In this article, the authors comment on the study "Coupling chemical mutagenesis to next generation sequencing for the identification of drug resistance mutations in Leishmania" by Bhattacharya et al. (Nat Commun, 2019), which introduces Mut-seq, a chemical mutagenesis and sequencing approach, to uncover drug resistance mechanisms in Leishmania, revealing links between lipid metabolism genes and miltefosine resistance, and a protein kinase involved in translation conferring paromomycin resistance.
Microfluidic techniques for separation of bacterial cells via taxis
January 15, 2020
Microfluidic tools, ideal for studying microbial motility due to their control over laminar flows at microscopic scales, enable precise analysis of various taxis behaviors and have advanced applications in synthetic biology, directed evolution, and medical microbiology.
Influence of delivery and feeding mode in oral fungi colonization – a systematic review
January 7, 2020
A systematic review of oral fungal colonization in infants found that while breastfeeding did not significantly affect the oral mycobiome, vaginal delivery was associated with higher oral yeast colonization, particularly of Candida albicans.
A holobiont view on thrombosis: unravelling the microbiota’s influence on arterial thrombus growth
January 6, 2020
In this article, the authors comment on the study "The microbiota promotes arterial thrombosis in low-density lipoprotein receptor-deficient mice" by Kiouptsi et al. (mBio, 2019) that showed that commensal microbiota, intricately linked to host physiology, may influence cardiovascular disease, as shown by studies using germ-free atherosclerosis-prone mice to examine how microbial presence and diet affect arterial thrombosis and lesion development.
The role of Lactobacillus species in the control of Candida via biotrophic interactions
November 25, 2019
Microbial communities, including Candida and Lactobacillus species, play a crucial role in human health, particularly in the context of mucosal infections, but our understanding of their interactions and effects is still incomplete due to the variability of species and isolates as well as the complexity of the human host.
Tribal warfare: Commensal Neisseria kill pathogen Neisseria gonorrhoeae using its DNA
October 19, 2019
This article comments on work published by Kim et al (Cell Host Microbe, 2019), which adds a new dimension to the concept of commensal protection. It shows that commensal Neisseria kill the closely related pathogen N. gonorrhoeae through an unexpected mechanism, one that involves genetic competence, DNA methylation state and recombination.
Yet another job for the bacterial ribosome
October 17, 2019
This article comments on work published by Knüpffer et al (mBio, 2019), which revealed the intricate interaction of uL23 with yet another essential player in bacteria, the ATPase SecA, which is best known for its role during post-translational secretion of proteins across the bacterial SecYEG translocon
Gut microbial metabolites in depression: understanding the biochemical mechanisms
September 27, 2019
This article shows how the gut microbiota contributes to the pathophysiology of depression and examines the mechanisms by which microbially-derived molecules may influence depressive behavior, highlighting the potential of dietary interventions as novel therapeutic strategies.
The multiple functions of the numerous Chlamydia trachomatis secreted proteins: the tip of the iceberg
August 21, 2019
CThis article shows an in-depth review on the current knowledge and outstanding questions about secreted proteins from Chlamydia trachomatis, detailing their roles in host cell interaction and immune response evasion.
Inhibiting eukaryotic ribosome biogenesis: Mining new tools for basic research and medical applications
August 20, 2019
This article comments on work published by Awad et al (BMC Biology, 2019), which screened for novel inhibitors of the ribosome biogenesis pathway in yeast.