Tuberculosis in otherwise healthy adults with inherited TNF deficiency.

Severe defects in human IFNγ immunity predispose individuals to both Bacillus Calmette-Guérin disease and tuberculosis, whereas milder defects predispose only to tuberculosis. Here we report two adults with recurrent pulmonary tuberculosis who are homozygous for a private loss-of-function TNF variant. Neither has any other clinical phenotype and both mount normal clinical and biological inflammatory responses.

Chalkophore mediated respiratory oxidase flexibility controls virulence.

Oxidative phosphorylation has emerged as a critical therapeutic vulnerability of (Mtb). However, it is unknown how intracellular bacterial pathogens such as Mtb maintain respiration during infection despite the chemical effectors of host immunity. synthesizes diisonitrile lipopeptides that tightly chelate copper, but the role of these chalkophores in host-pathogen interactions is also unknown.

Structure of the M. tuberculosis DnaK-GrpE complex reveals how key DnaK roles are controlled.

The molecular chaperone DnaK is essential for viability of Mycobacterium tuberculosis (Mtb). DnaK hydrolyzes ATP to fold substrates, and the resulting ADP is exchanged for ATP by the nucleotide exchange factor GrpE. It has been unclear how GrpE couples DnaK's nucleotide exchange with substrate release.

Commensal antimicrobial resistance mediates microbiome resilience to antibiotic disruption.

Despite their therapeutic benefits, antibiotics exert collateral damage on the microbiome and promote antimicrobial resistance. However, the mechanisms governing microbiome recovery from antibiotics are poorly understood. Treatment of , the world's most common infection, represents the longest antimicrobial exposure in humans.

WNK1 enforces macrophage lineage fidelity.

Unlabelled: The appropriate development of macrophages, the body's professional phagocyte, is essential for organismal development, especially in mammals. This dependence is exemplified by the observation that loss-of-function mutations in colony stimulating factor 1 receptor (CSF1R) results in multiple tissue abnormalities owing to an absence of macrophages. Despite this importance, little is known about the molecular and cell biological regulation of macrophage development.

Roles for mycobacterial DinB2 in frameshift and substitution mutagenesis.

Translesion synthesis by translesion polymerases is a conserved mechanism of DNA damage tolerance. In bacteria, DinB enzymes are the widely distributed promutagenic translesion polymerases. The role of DinBs in mycobacterial mutagenesis was unclear until recent studies revealed a role for mycobacterial DinB1 in substitution and frameshift mutagenesis, overlapping with that of translesion polymerase DnaE2.

The C-Terminal Acid Phosphatase Module of the RNase HI Enzyme RnhC Controls Rifampin Sensitivity and Light-Dependent Colony Pigmentation of Mycobacterium smegmatis.

RNase H enzymes participate in various processes that require processing of RNA-DNA hybrids, including DNA replication, transcription, and ribonucleotide excision from DNA. Mycobacteria encode multiple RNase H enzymes, and prior data indicate that RNase HI activity is essential for mycobacterial viability. However, the additional roles of mycobacterial RNase Hs are unknown, including whether RNase HII (RnhB and RnhD) excises chromosomal ribonucleotides misincorporated during DNA replication and whether individual RNase HI enzymes (RnhA and RnhC) mediate additional phenotypes.

Mycobacterial helicase Lhr abets resistance to DNA crosslinking agents mitomycin C and cisplatin.

Mycobacterium smegmatis Lhr exemplifies a novel clade of helicases composed of an N-terminal ATPase/helicase domain (Lhr-Core) and a large C-terminal domain (Lhr-CTD) that nucleates a unique homo-tetrameric quaternary structure. Expression of Lhr, and its operonic neighbor Nei2, is induced in mycobacteria exposed to mitomycin C (MMC). Here we report that lhr deletion sensitizes M.

Diisonitrile Lipopeptides Mediate Resistance to Copper Starvation in Pathogenic Mycobacteria.

Bacterial pathogens and their hosts engage in intense competition for critical nutrients during infection, including metals such as iron, copper, and zinc. Some metals are limited by the host, and some are deployed by the host as antimicrobials. To counter metal limitation, pathogens deploy high-affinity metal acquisition systems, best exemplified by siderophores to acquire iron.

BCG-Induced Tumor Immunity Requires Tumor-Intrinsic CIITA Independent of MHC-II.

For decades, BCG immunotherapy has been the standard of care for non-muscle-invasive bladder cancer. Despite this clinical experience, the mechanism by which BCG stimulates tumor-eliminating immunity is unclear, and there is still a need for more accurate prediction of clinical outcomes in advance of treatment initiation. We have shown that BCG stimulates tumor-specific T-cell immunity that requires tumor cell expression of the IFNγ receptor (IFNGR); however, the downstream components of IFNGR signaling responsible for responsiveness to BCG are unknown.

Distinctive roles of translesion polymerases DinB1 and DnaE2 in diversification of the mycobacterial genome through substitution and frameshift mutagenesis.

Antibiotic resistance of Mycobacterium tuberculosis is exclusively a consequence of chromosomal mutations. Translesion synthesis (TLS) is a widely conserved mechanism of DNA damage tolerance and mutagenesis, executed by translesion polymerases such as DinBs. In mycobacteria, DnaE2 is the only known agent of TLS and the role of DinB polymerases is unknown.

Single-Cell Transcriptional Profiling Reveals Signatures of Helper, Effector, and Regulatory MAIT Cells during Homeostasis and Activation.

Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that recognize microbial vitamin B metabolites and have emerging roles in infectious disease, autoimmunity, and cancer. Although MAIT cells are identified by a semi-invariant TCR, their phenotypic and functional heterogeneity is not well understood. Here we present an integrated single cell transcriptomic analysis of over 76,000 human MAIT cells during early and prolonged Ag-specific activation with the MR1 ligand 5-OP-RU and nonspecific TCR stimulation.

Division of labor between SOS and PafBC in mycobacterial DNA repair and mutagenesis.

DNA repair systems allow microbes to survive in diverse environments that compromise chromosomal integrity. Pathogens such as Mycobacterium tuberculosis must contend with the genotoxic host environment, which generates the mutations that underlie antibiotic resistance. Mycobacteria encode the widely distributed SOS pathway, governed by the LexA repressor, but also encode PafBC, a positive regulator of the transcriptional DNA damage response (DDR).

Inherited PD-1 deficiency underlies tuberculosis and autoimmunity in a child.

The pathophysiology of adverse events following programmed cell death protein 1 (PD-1) blockade, including tuberculosis (TB) and autoimmunity, remains poorly characterized. We studied a patient with inherited PD-1 deficiency and TB who died of pulmonary autoimmunity. The patient's leukocytes did not express PD-1 or respond to PD-1-mediated suppression.

Structural basis for aggregate dissolution and refolding by the Mycobacterium tuberculosis ClpB-DnaK bi-chaperone system.

The M. tuberculosis (Mtb) ClpB is a protein disaggregase that helps to rejuvenate the bacterial cell. DnaK is a protein foldase that can function alone, but it can also bind to the ClpB hexamer to physically couple protein disaggregation with protein refolding, although the molecular mechanism is not well understood.

Integrated sensing of host stresses by inhibition of a cytoplasmic two-component system controls acute lung infection.

Bacterial pathogens that infect phagocytic cells must deploy mechanisms that sense and neutralize host microbicidal effectors. For , the causative agent of tuberculosis, these mechanisms allow the bacterium to rapidly adapt from aerosol transmission to initial growth in the lung alveolar macrophage. Here, we identify a branched signaling circuit in that controls growth in the lung through integrated direct sensing of copper ions and nitric oxide by coupled activity of the Rip1 intramembrane protease and the PdtaS/R two-component system.

The DnaK Chaperone System Buffers the Fitness Cost of Antibiotic Resistance Mutations in Mycobacteria.

Chaperones aid in protein folding and maintenance of protein integrity. In doing so, they have the unique ability to directly stabilize resistance-conferring amino acid substitutions in drug targets and to counter the stress imparted by these substitutions, thus supporting heritable antimicrobial resistance (AMR). We asked whether chaperones support AMR in , a saprophytic model of , the causative agent of tuberculosis (TB).

Gastrointestinal microbiota composition predicts peripheral inflammatory state during treatment of human tuberculosis.

The composition of the gastrointestinal microbiota influences systemic immune responses, but how this affects infectious disease pathogenesis and antibiotic therapy outcome is poorly understood. This question is rarely examined in humans due to the difficulty in dissociating the immunologic effects of antibiotic-induced pathogen clearance and microbiome alteration. Here, we analyze data from two longitudinal studies of tuberculosis (TB) therapy (35 and 20 individuals) and a cross sectional study from 55 healthy controls, in which we collected fecal samples (for microbiome analysis), sputum (for determination of Mycobacterium tuberculosis (Mtb) bacterial load), and peripheral blood (for transcriptomic analysis).

Efficient 5-OP-RU-Induced Enrichment of Mucosa-Associated Invariant T Cells in the Murine Lung Does Not Enhance Control of Aerosol Mycobacterium tuberculosis Infection.

Mucosa-associated invariant T (MAIT) cells are an innate-like T cell subset in mammals that recognize microbial vitamin B metabolites presented by the evolutionarily conserved major histocompatibility complex class I (MHC I)-related molecule, MR1. Emerging data suggest that MAIT cells may be an attractive target for vaccine-induced protection against bacterial infections because of their rapid cytotoxic responses at mucosal services to a widely conserved bacterial ligand. In this study, we tested whether a MAIT cell priming strategy could protect against aerosol infection in mice.

A multilayered repair system protects the mycobacterial chromosome from endogenous and antibiotic-induced oxidative damage.

Oxidative damage to DNA is a threat to the genomic integrity and coding accuracy of the chromosomes of all living organisms. Guanine is particularly susceptible to oxidation, and 8-oxo-dG (OG), when produced in situ or incorporated by DNA polymerases, is highly mutagenic due to mispairing with adenine. In many bacteria, defense against OG depends on MutT enzymes, which sanitize OG in the nucleotide pool, and the MutM/Y system, which counteracts OG in chromosomal DNA.

Bacterial immunotherapy for cancer induces CD4-dependent tumor-specific immunity through tumor-intrinsic interferon-γ signaling.

Bacillus Calmette-Guérin (BCG) immunotherapy for bladder cancer is the only bacterial cancer therapy approved for clinical use. Although presumed to induce T cell-mediated immunity, whether tumor elimination depends on bacteria-specific or tumor-specific immunity is unknown. Herein we show that BCG-induced bladder tumor elimination requires CD4 and CD8 T cells, although augmentation or inhibition of bacterial antigen-specific T cell responses does not alter the efficacy of BCG-induced tumor elimination.

Two Accessory Proteins Govern MmpL3 Mycolic Acid Transport in Mycobacteria.

Mycolic acids are the signature lipid of mycobacteria and constitute an important physical component of the cell wall, a target of mycobacterium-specific antibiotics and a mediator of pathogenesis. Mycolic acids are synthesized in the cytoplasm and are thought to be transported to the cell wall as a trehalose ester by the MmpL3 transporter, an antibiotic target for However, the mechanism by which mycolate synthesis is coupled to transport, and the full MmpL3 transport machinery, is unknown. Here, we identify two new components of the MmpL3 transport machinery in mycobacteria.