Certain methanogens deteriorate steel surfaces through a process called microbiologically influenced corrosion (MIC). However, the mechanisms of MIC, whereby methanogens oxidize zerovalent iron (Fe0), are largely unknown. In this study, Fe0-corroding Methanococcus maripaludis strain OS7 and its derivative (strain OS7mut1) defective in Fe0-corroding activity were isolated. Genomic analysis of these strains demonstrated that the strain OS7mut1 contained a 12-kb chromosomal deletion. The deleted region, termed “MIC island”, encoded the genes for the large and small subunits of a [NiFe] hydrogenase, the TatA/TatC genes necessary for the secretion of the [NiFe] hydrogenase, and a gene for the hydrogenase maturation protease. Thus, the [NiFe] hydrogenase may be secreted outside the cytoplasmic membrane, where the [NiFe] hydrogenase can make direct contact with Fe0, and oxidize it, generating hydrogen gas: Fe0 + 2 H+ → Fe2+ + H2. Comparative analysis of extracellular and intracellular proteomes of strain OS7 supported this hypothesis. The identification of the MIC genes enables the development of molecular tools to monitor epidemiology, and to perform surveillance and risk assessment of MIC-inducing M. maripaludis.

The soil actinomycete Kocuria rhizophila belongs to the suborder Micrococcineae, a divergent bacterial group for which only a limited amount of genomic information is currently available. K. rhizophila is also important in industrial applications; e.g., it is commonly used as a standard quality control strain for antimicrobial susceptibility testing. Sequencing and annotation of the genome of K. rhizophila DC2201 (NBRC 103217) revealed a single circular chromosome (2,697,540 bp; G؉C content of 71.16%) containing 2,357 predicted protein-coding genes. Most of the predicted proteins (87.7%) were orthologous to actinobacterial proteins, and the genome showed fairly good conservation of synteny with taxonomically related actinobacterial genomes. On the other hand, the genome seems to encode much smaller numbers of proteins necessary for secondary metabolism (one each of nonribosomal peptide synthetase and type III polyketide synthase), transcriptional regulation, and lateral gene transfer, reflecting the small genome size. The presence of probable metabolic pathways for the transformation of phenolic compounds generated from the decomposition of plant materials, and the presence of a large number of genes associated with membrane transport, particularly amino acid transporters and drug efflux pumps, may contribute to the organism's utilization of root exudates, as well as the tolerance to various organic compounds.

PurposeTo investigate the characteristics of uveitic glaucoma (UG) and evaluate surgical treatments.MethodsThis study examined a retrospective, nonrandomized comparative interventional case series of 105 UG patients (141 eyes) followed between April 1, 2001 and July 30, 2014 at the outpatient clinic of Tohoku University Hospital. The study group included 47 patients (47 eyes) who underwent glaucoma surgery: trabeculectomy, trabeculotomy, and trabectome surgery. The analysis used Kaplan–Meier life tables, with surgical failure defined as intraocular pressure ≧21 mmHg or the need for additional glaucoma surgery.ResultsUG patients represented 9.73% of our database of glaucoma patients. The mean follow-up period was 40.32±32.53 months. Seventy-one patients had granulomatous uveitis (67.62%) and 34 had nongranulomatous uveitis (32.38%). The causes of uveitis included sarcoidosis (n=25), Behçet’s disease (n=11), Vogt–Koyanagi–Harada disease (n=9), Posner–Schlossman syndrome (n=12), herpes simplex virus infectious uveitis (n=7), acute anterior uveitis (n=5), intermediate uveitis (n=4), scleritis (n=4), inflammatory bowel disease (n=4), varicella zoster virus uveitis (n=2), and others (n=6). An additional 16 patients were diagnosed with idiopathic UG. Surgical success rates were 82.86% for trabeculectomy, 62.50% for trabeculotomy, and 75.00% for trabectome. Significant risk factors for surgical failure included male sex (P=0.02), age less than 45 years (P=0.0009), nongranulomatous uveitis (P=0.04), and postoperative inflammation (P=0.01).ConclusionYoung male patients with nongranulomatous uveitis had a significant risk of surgical failure. Moreover, prolonged postoperative inflammation created a susceptibility to surgical failure, indicating the importance of postoperative inflammation reduction.

No abstract