Rapid Concentration and Detection of Bacteria in Milk Using a Microfluidic Surface Acoustic Wave Activated Nanosieve.

Rapid detection of microbes is a key feature for monitoring food quality. Unfortunately, current detection systems rely on labor-intensive and time-consuming lab-based processes that are not suitable for point-of-interest applications and typically require several days before results are available. Here, we demonstrate a microfluidic system capable of rapidly concentrating, fluorescent staining, and detecting bacteria in unprocessed complex biological media such as milk.

Microorganisms oxidize glucose through distinct pathways in permeable and cohesive sediments.

In marine sediments, microbial degradation of organic matter under anoxic conditions is generally thought to proceed through fermentation to volatile fatty acids, which are then oxidized to CO2 coupled to the reduction of terminal electron acceptors (e.g. nitrate, iron, manganese, and sulfate).

Extensive genome analysis identifies novel plasmid families in .

Globally, the anaerobic bacterium causes severe disease in a wide array of hosts; however, strains are also carried asymptomatically. Accessory genes are responsible for much of the observed phenotypic variation and virulence within this species, with toxins frequently encoded on conjugative plasmids and many isolates carrying up to 10 plasmids. Despite this unusual biology, current genomic analyses have largely excluded isolates from healthy hosts or environmental sources.

Molecular hydrogen in seawater supports growth of diverse marine bacteria.

Molecular hydrogen (H) is an abundant and readily accessible energy source in marine systems, but it remains unknown whether marine microbial communities consume this gas. Here we use a suite of approaches to show that marine bacteria consume H to support growth. Genes for H-uptake hydrogenases are prevalent in global ocean metagenomes, highly expressed in metatranscriptomes and found across eight bacterial phyla.

Simultaneous detection of multiple pathogens with the TaqMan Array Card.

Quantitative polymerase chain reaction (qPCR) is a gold standard method for the detection and quantification of pathogenic organisms. Standard qPCR is inexpensive, sensitive and highly specific to the pathogen of interest. While qPCR assays can be multiplexed to allow the detection of multiple organisms in one reaction, it is prohibitively labour intensive to screen large numbers of samples for several pathogens at the same time.

Multiple energy sources and metabolic strategies sustain microbial diversity in Antarctic desert soils.

Numerous diverse microorganisms reside in the cold desert soils of continental Antarctica, though we lack a holistic understanding of the metabolic processes that sustain them. Here, we profile the composition, capabilities, and activities of the microbial communities in 16 physicochemically diverse mountainous and glacial soils. We assembled 451 metagenome-assembled genomes from 18 microbial phyla and inferred through Bayesian divergence analysis that the dominant lineages present are likely native to Antarctica.

Termite gas emissions select for hydrogenotrophic microbial communities in termite mounds.

Organoheterotrophs are the dominant bacteria in most soils worldwide. While many of these bacteria can subsist on atmospheric hydrogen (H), levels of this gas are generally insufficient to sustain hydrogenotrophic growth. In contrast, bacteria residing within soil-derived termite mounds are exposed to high fluxes of H due to fermentative production within termite guts.

Monitoring of diverse enteric pathogens across environmental and host reservoirs with TaqMan array cards and standard qPCR: a methodological comparison study.

Background: Multiple bacteria, viruses, protists, and helminths cause enteric infections that greatly impact human health and wellbeing. These enteropathogens are transmited via several pathways through human, animal, and environmental reservoirs. Individual qPCR assays have been extensively used to detect enteropathogens within these types of samples, whereas the TaqMan array card (TAC), which allows simultaneous detection of multiple enteropathogens, has only previously been validated in human clinical samples.

Termite mounds contain soil-derived methanotroph communities kinetically adapted to elevated methane concentrations.

Termite mounds have recently been confirmed to mitigate approximately half of termite methane (CH) emissions, but the aerobic CH oxidising bacteria (methanotrophs) responsible for this consumption have not been resolved. Here, we describe the abundance, composition and CH oxidation kinetics of the methanotroph communities in the mounds of three distinct termite species sampled from Northern Australia. Results from three independent methods employed show that methanotrophs are rare members of microbial communities in termite mounds, with a comparable abundance but distinct composition to those of adjoining soil samples.

Two Chloroflexi classes independently evolved the ability to persist on atmospheric hydrogen and carbon monoxide.

Most aerobic bacteria exist in dormant states within natural environments. In these states, they endure adverse environmental conditions such as nutrient starvation by decreasing metabolic expenditure and using alternative energy sources. In this study, we investigated the energy sources that support persistence of two aerobic thermophilic strains of the environmentally widespread but understudied phylum Chloroflexi.

Cofactor Tail Length Modulates Catalysis of Bacterial F-Dependent Oxidoreductases.

F is a microbial cofactor that mediates a wide range of physiologically important and industrially relevant redox reactions, including in methanogenesis and tetracycline biosynthesis. This deazaflavin comprises a redox-active isoalloxazine headgroup conjugated to a lactyloligoglutamyl tail. Here we studied the catalytic significance of the oligoglutamate chain, which differs in length between bacteria and archaea.

Mycobacterial FH-Dependent Reductases Promiscuously Reduce Diverse Compounds through a Common Mechanism.

An unusual aspect of actinobacterial metabolism is the use of the redox cofactor F. Studies have shown that actinobacterial FH-dependent reductases promiscuously hydrogenate diverse organic compounds in biodegradative and biosynthetic processes. These enzymes therefore represent promising candidates for next-generation industrial biocatalysts.

The Redox Cofactor F Protects Mycobacteria from Diverse Antimicrobial Compounds and Mediates a Reductive Detoxification System.

A defining feature of mycobacterial redox metabolism is the use of an unusual deazaflavin cofactor, F This cofactor enhances the persistence of environmental and pathogenic mycobacteria, including after antimicrobial treatment, although the molecular basis for this remains to be understood. In this work, we explored our hypothesis that F enhances persistence by serving as a cofactor in antimicrobial-detoxifying enzymes. To test this, we performed a series of phenotypic, biochemical, and analytical chemistry studies in relation to the model soil bacterium Mutant strains unable to synthesize or reduce F were found to be more susceptible to a wide range of antibiotic and xenobiotic compounds.