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d support cell division in E. coli Chlamydial RodZ plays a major role in directing chlamydial MreB localization to the cell division site. It is likely that the evolution of chlamydial MreB and RodZ to form a functional cell division complex allowed Chlamydia to dispense with its FtsZ-based cell division machinery during genome reduction. Thus, MreB-RodZ represents a possible mechanism for cell division in other bacteria lacking FtsZ. Copyright © 2020 Ranjit et al.Pathogenic bacteria need high-affinity zinc uptake systems to counteract the nutritional immunity exerted by infected hosts. However, our understanding of zinc homeostasis in mutualistic systems such as the rhizobium-legume symbiosis is limited. Here, we show that the conserved high-affinity zinc transporter ZnuABC and accessory transporter proteins (Zip1, Zip2, and c06450) made cumulative contributions to nodulation of the broad-host-range strain Sinorhizobium fredii CCBAU45436. Zur acted as a zinc-dependent repressor for the znuC-znuB-zur operon, znuA, and c06450 by binding to the associated Zur box, but did not regulate zip1 and zip2 ZnuABC was the major zinc transporter. Combined mutants lacking znuA and one of the three accessory genes had more severe defects in nodulation and growth under zinc starvation conditions than the znuA mutant, though rhizoplane colonization by these mutants was not impaired. In contrast to the elite strain CCBAU45436, more drastic symbiotic defects were observed for the znuA my among legume cultivars, field sites, and years. These long-lasting challenging problems impede the establishment of a sustainable agriculture, particularly in developing countries. Here, we report that rhizobial zinc starvation machinery containing a conserved high-affinity zinc transporter and accessory components makes cumulative contributions to modulating rhizobial symbiotic compatibility. This work highlights a critical role of largely unexplored nutritional immunity in the rhizobium-legume symbiosis, which makes zinc starvation machinery an attractive target for improving rhizobial symbiotic compatibility. Copyright © 2020 Zhang et al.Colorectal adenomas are precancerous lesions of colorectal cancer (CRC) that offer a means of viewing the events key to early CRC development. A number of studies have investigated the changes and roles of gut microbiota in adenoma and carcinoma development, highlighting its impact on carcinogenesis. However, there has been less of a focus on the gut metabolome, which mediates interactions between the host and gut microbes. Here, we investigated metabolomic profiles of stool samples from patients with advanced adenoma (n = 102), matched controls (n = 102), and patients with CRC (n = 36). We found that several classes of bioactive lipids, including polyunsaturated fatty acids, secondary bile acids, and sphingolipids, were elevated in the adenoma patients compared to the controls. compound library chemical Most such metabolites showed directionally consistent changes in the CRC patients, suggesting that those changes may represent early events of carcinogenesis. We also examined gut microbiome-metabolome associations using gut microbiotsignatures of colorectal adenoma that were associated with some gut microbes and potentially indicative of future CRC. This study highlights potential early-driver metabolites in CRC pathogenesis and guides further targeted experiments and thus provides an important stepping stone toward developing better CRC prevention strategies. Copyright © 2020 Kim et al.Staphylococcus epidermidis is a leading cause of nosocomial infections in patients with a compromised immune system and/or an implanted medical device. Seventy to 90% of S. epidermidis clinical isolates are methicillin resistant and carry the mecA gene, present in a mobile genetic element (MGE) called the staphylococcal cassette chromosome mec (SCCmec) element. Along with the presence of antibiotic and heavy metal resistance genes, MGEs can also contain genes encoding secreted or cell wall-anchored virulence factors. In our earlier studies of S. epidermidis clinical isolates, we discovered S. epidermidis surface protein J (SesJ), a prototype of a recently discovered subfamily of the microbial surface component recognizing adhesive matrix molecule (MSCRAMM) group. MSCRAMMs are major virulence factors of pathogenic Gram-positive bacteria. Here, we report that the sesJ gene is always accompanied by two glycosyltransferase genes, gtfA and gtfB, and is present in two MGEs, called the arginine catabolic mobile elems provides an example of such pathogen adaptation. With limited opportunities to modify the core genome, most of the adaptation occurs by acquiring new genes, such as virulence factors and antibiotic resistance determinants present in MGEs. In this study, we describe that the sesJ gene, encoding a recently discovered cell wall-anchored protein in S. epidermidis, is present in both ACME and the SCC element. The presence of virulence factors in MGEs can influence the virulence potential of a specific strain. Therefore, it is critical to study the virulence factors found in MGEs in emerging pathogenic bacteria or strains to understand the mechanisms used by these bacteria to cause infections. Copyright © 2020 Arora et al.The presence of CpG and UpA dinucleotides is restricted in the genomes of animal RNA viruses to avoid specific host defenses. We wondered whether a similar phenomenon exists in nonanimal RNA viruses. Here, we show that these two dinucleotides, especially UpA, are underrepresented in the family Potyviridae, the most important group of plant RNA viruses. Using plum pox virus (PPV; Potyviridae family) as a model, we show that an increase in UpA frequency strongly diminishes virus accumulation. Remarkably, unlike previous observations in animal viruses, PPV variants harboring CpG-rich fragments display just faint (or no) attenuation. The anticorrelation between UpA frequency and viral fitness additionally demonstrates the relevance of this particular dinucleotide UpA-high mutants are attenuated in a dose-dependent manner, whereas a UpA-low variant displays better fitness than its parental control. Using high-throughput sequencing, we also show that UpA-rich PPV variants are genetically stable, without apparent changes in sequence that revert and/or compensate for the dinucleotide modification despite its attenuation.