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Matrix stones are a rare form of kidney stones. They feature a high percentage of hydrogel-like organic matter, and their formation is closely associated with urinary tract infections. Herein, comprehensive materials and biochemical approaches were taken to map the organic-inorganic interface and gather insights into the host-microbe interplay in pathological renal biomineralization. Surgically extracted soft and slimy matrix stones were examined using micro-X-ray computed tomography and various microspectroscopy techniques. Higher-mineral-density laminae were positive for calcium-bound Alizarin red. Lower-mineral-density laminae revealed periodic acid-Schiff-positive organic filamentous networks of varied thickness. These organic filamentous networks, which featured a high polysaccharide content, were enriched with zinc, carbon, and sulfur elements. Neutrophil extracellular traps (NETs) along with immune response-related proteins, including calprotectin, myeloperoxidase, CD63, and CD86, also were identified in the filamentous networks. Expressions of NETs and upregulation of polysaccharide-rich mucin secretion are proposed as a part of the host immune defense to "trap" pathogens. These host-microbe derived organic matrices can facilitate heterogeneous nucleation and precipitation of inorganic particulates, resulting in macroscale aggregates known as "matrix stones". These insights into the plausible aggregation of constituents through host-microbe interplay underscore the unique "double-edged sword" effect of the host immune response to pathogens and the resulting renal biominerals.

Molecular biology methods and technologies have advanced substantially over the past decade. These new molecular methods should be incorporated among the standard tools of planetary protection (PP) and could be validated for incorporation by 2026. To address the feasibility of applying modern molecular techniques to such an application, NASA conducted a technology workshop with private industry partners, academics, and government agency stakeholders, along with NASA staff and contractors. The technical discussions and presentations of the Multi-Mission Metagenomics Technology Development Workshop focused on modernizing and supplementing the current PP assays. The goals of the workshop were to assess the state of metagenomics and other advanced molecular techniques in the context of providing a validated framework to supplement the bacterial endospore-based NASA Standard Assay and to identify knowledge and technology gaps. In particular, workshop participants were tasked with discussing metagenomics as a stand-alone technology to provide rapid and comprehensive analysis of total nucleic acids and viable microorganisms on spacecraft surfaces, thereby allowing for the development of tailored and cost-effective microbial reduction plans for each hardware item on a spacecraft. Workshop participants recommended metagenomics approaches as the only data source that can adequately feed into quantitative microbial risk assessment models for evaluating the risk of forward (exploring extraterrestrial planet) and back (Earth harmful biological) contamination. Participants were unanimous that a metagenomics workflow, in tandem with rapid targeted quantitative (digital) PCR, represents a revolutionary advance over existing methods for the assessment of microbial bioburden on spacecraft surfaces. The workshop highlighted low biomass sampling, reagent contamination, and inconsistent bioinformatics data analysis as key areas for technology development. Finally, it was concluded that implementing metagenomics as an additional workflow for addressing concerns of NASA's robotic mission will represent a dramatic improvement in technology advancement for PP and will benefit future missions where mission success is affected by backward and forward contamination.

To understand the health impact of long-duration spaceflight, one identical twin astronaut was monitored before, during, and after a 1-year mission onboard the International Space Station; his twin served as a genetically matched ground control. Longitudinal assessments identified spaceflight-specific changes, including decreased body mass, telomere elongation, genome instability, carotid artery distension and increased intima-media thickness, altered ocular structure, transcriptional and metabolic changes, DNA methylation changes in immune and oxidative stress-related pathways, gastrointestinal microbiota alterations, and some cognitive decline postflight. Although average telomere length, global gene expression, and microbiome changes returned to near preflight levels within 6 months after return to Earth, increased numbers of short telomeres were observed and expression of some genes was still disrupted. These multiomic, molecular, physiological, and behavioral datasets provide a valuable roadmap of the putative health risks for future human spaceflight.

We report the whole-genome sequence of Muricauda sp. strain K001 isolated from a marine cyanobacterial culture. This genome sequence will improve our understanding of the influence of heterotrophic bacteria on the physiology of cyanobacteria and may contribute to the development of new natural products.

The Extreme Microbiome Project (XMP) is a project launched by the Association of Biomolecular Resource Facilities Metagenomics Research Group (ABRF MGRG) that focuses on whole genome shotgun sequencing of extreme and unique environments using a wide variety of biomolecular techniques. The goals are multifaceted, including development and refinement of new techniques for the following: 1) the detection and characterization of novel microbes, 2) the evaluation of nucleic acid techniques for extremophilic samples, and 3) the identification and implementation of the appropriate bioinformatics pipelines. Here, we highlight the different ongoing projects that we have been working on, as well as details on the various methods we use to characterize the microbiome and metagenome of these complex samples. In particular, we present data of a novel multienzyme extraction protocol that we developed, called Polyzyme or MetaPolyZyme. Presently, the XMP is characterizing sample sites around the world with the intent of discovering new species, genes, and gene clusters. Once a project site is complete, the resulting data will be publically available. Sites include Lake Hillier in Western Australia, the "Door to Hell" crater in Turkmenistan, deep ocean brine lakes of the Gulf of Mexico, deep ocean sediments from Greenland, permafrost tunnels in Alaska, ancient microbial biofilms from Antarctica, Blue Lagoon Iceland, Ethiopian toxic hot springs, and the acidic hypersaline ponds in Western Australia.

Oral neomycin administration impacts the gut microbiome and delays vitiligo development in mice, and topical antibiotics may likewise allow the microbiome to preserve skin health and delay depigmentation. Here, we examined the effects of 6‐week topical antibiotic treatment on vitiligo‐prone pmel‐1 mice. Bacitracin, Neosporin, or Vaseline were applied to one denuded flank, while the contralateral flank was treated with Vaseline in all mice. Ventral depigmentation was quantified weekly. We found that topical Neosporin treatment significantly reduced depigmentation and exhibited effects beyond the treated area, while Bacitracin ointment had no effect. Stool samples collected from four representative mice/group during treatment revealed that Neosporin treatment aligned with reduced abundance of the Alistipes genus in the gut, while relevant changes to the skin microbiome at end point were less apparent. Either antibiotic treatment led to reduced expression of MR1, potentially limiting mucosal‐associated invariant T‐cell activation, while Neosporin‐treated skin selectively revealed significantly reduced CD8+ T‐cell abundance. The latter finding aligned with reduced expression of multiple inflammatory markers and markedly increased regulatory T‐cell density. Our studies on favorable skin and oral antibiotic treatment share the neomycin compound, and in either case, microbial changes were most apparent in stool samples. Taken together, neomycin‐containing antibiotic applications can mediate skin Treg infiltration to limit vitiligo development. Our study highlights the therapeutic potential of short‐term antibiotic applications to limit depigmentation vitiligo. [ABSTRACT FROM AUTHOR]

When the polymerase chain reaction (PCR) is used to amplify complex templates such as metagenomic DNA using single or degenerate primers, preferential amplification of templates (PCR bias) leads to a distorted representation of the original templates in the final amplicon pool. This bias can be influenced by mismatches between primers and templates, the locations of mismatches, and the nucleotide pairing of mismatches. Many studies have examined primer-template interactions through interrogation of the final products of PCR amplification with controlled input templates. Direct measurement of primer-template interactions, however, has not been possible, leading to uncertainty when optimizing PCR reactions and degenerate primer pools. In this study, we employed a method developed to reduce PCR bias (i.e., Deconstructed PCR, or DePCR) that also provides empirical data regarding primer-template interactions during the first two cycles of PCR amplification. We systematically examined interactions between primers and templates using synthetic DNA templates and varying primer pools, amplified using standard PCR and DePCR protocols. We observed that in simple primer-template systems, perfect match primer-template interactions are favored, particularly when mismatches are close to the 3′ end of the primer. In more complex primer-template systems that better represent natural samples, mismatch amplifications can dominate, and heavily degenerate primer pools can improve representation of input templates. When employing the DePCR methodology, mismatched primer-template annealing led to amplification of source templates with significantly lower distortion relative to standard PCR. We establish here a quantitative experimental system for interrogating primer-template interactions and demonstrate the efficacy of DePCR for amplification of complex template mixtures with complex primer pools. [ABSTRACT FROM AUTHOR]

UnlabelledUnraveling the drivers controlling the response and adaptation of biological communities to environmental change, especially anthropogenic activities, is a central but poorly understood issue in ecology and evolution. Comparative genomics studies suggest that lateral gene transfer (LGT) is a major force driving microbial genome evolution, but its role in the evolution of microbial communities remains elusive. To delineate the importance of LGT in mediating the response of a groundwater microbial community to heavy metal contamination, representative Rhodanobacter reference genomes were sequenced and compared to shotgun metagenome sequences. 16S rRNA gene-based amplicon sequence analysis indicated that Rhodanobacter populations were highly abundant in contaminated wells with low pHs and high levels of nitrate and heavy metals but remained rare in the uncontaminated wells. Sequence comparisons revealed that multiple geochemically important genes, including genes encoding Fe(2+)/Pb(2+) permeases, most denitrification enzymes, and cytochrome c553, were native to Rhodanobacter and not subjected to LGT. In contrast, the Rhodanobacter pangenome contained a recombinational hot spot in which numerous metal resistance genes were subjected to LGT and/or duplication. In particular, Co(2+)/Zn(2+)/Cd(2+) efflux and mercuric resistance operon genes appeared to be highly mobile within Rhodanobacter populations. Evidence of multiple duplications of a mercuric resistance operon common to most Rhodanobacter strains was also observed. Collectively, our analyses indicated the importance of LGT during the evolution of groundwater microbial communities in response to heavy metal contamination, and a conceptual model was developed to display such adaptive evolutionary processes for explaining the extreme dominance of Rhodanobacter populations in the contaminated groundwater microbiome.ImportanceLateral gene transfer (LGT), along with positive selection and gene duplication, are the three main mechanisms that drive adaptive evolution of microbial genomes and communities, but their relative importance is unclear. Some recent studies suggested that LGT is a major adaptive mechanism for microbial populations in response to changing environments, and hence, it could also be critical in shaping microbial community structure. However, direct evidence of LGT and its rates in extant natural microbial communities in response to changing environments is still lacking. Our results presented in this study provide explicit evidence that LGT played a crucial role in driving the evolution of a groundwater microbial community in response to extreme heavy metal contamination. It appears that acquisition of genes critical for survival, growth, and reproduction via LGT is the most rapid and effective way to enable microorganisms and associated microbial communities to quickly adapt to abrupt harsh environmental stresses.

Adolescent girls bear a disproportionate burden of both the HIV epidemic and unintended pregnancies; yet important questions remain unanswered regarding the effects of hormonal contraceptives on the vaginal immune microenvironment, which can impact HIV susceptibility in this group. Multiple studies report genital immune alterations associated with the progestin-based contraceptive Depot medroxyprogesterone acetate (DMPA) in adult women, but there is little available data in adolescents. The objective of this longitudinal cohort study was to evaluate the effects of short-term use of three progestin-based contraceptives, levonorgestrel intrauterine device (LNG-IUD), subdermal etonogestrel (ETNG), and injectable DMPA, on HIV-associated vaginal immune biomarkers and microbiome in adolescent girls. Fifty-nine sexually active, HIV-uninfected girls aged 15-19, were recruited from the Washington DC metro area and self-selected into Control (condoms only), combined oral contraceptive pills, LNG-IUD, ETNG and DMPA groups. Vaginal swabs were collected at baseline prior to contraceptive use and at 3-month follow-up visit. Vaginal secretions were tested for pro-inflammatory (IL-1α, IL-1β, TNF-α, IL-6, IL-8, MIP-3α, IP-10, RANTES, MIP-1α, MIP-1β) and anti-inflammatory/anti-HIV (Serpin-A1, Elafin, Beta-Defensin-2, SLPI) immune biomarkers using ELISA and for anti-HIV activity using TZM-bl assay. Vaginal microbiome was evaluated using 16S rRNA gene sequencing. Data were analyzed using SAS Version 9. Among the 34 participants who completed both visits, no significant changes in median biomarker concentrations, HIV inhibition and microbiome composition were observed between baseline and follow-up visits for any of the contraceptive groups. IL-8 (p<0.01), MIP-3α (0.02), Elafin (p = 0.03) and RANTES (p<0.01) differed significantly by race whereas IL-6 was significantly different by age (p = 0.03). We conclude that 3-month use of LNG-IUD, ETNG and DMPA have minimal effects on adolescent vaginal immune microenvironment, and therefore unlikely to impact HIV risk. Future studies with larger sample size and longer follow-up are recommended to continue to evaluate effects of contraceptives on the lower genital tract immunity and susceptibility to sexually transmitted infections. [ABSTRACT FROM AUTHOR]