H ydrogenophilalia

• Main Authors: Boden, Rich, Hutt, Lee P, Rae, Alex
• Format: Other/Unknown Material
• Language: English
• Published: Wiley 2019
• Subjects: Iceland
• Online Access: http://dx.doi.org/10.1002/9781118960608.cbm00080; https://onlinelibrary.wiley.com/doi/pdf/10.1002/9781118960608.cbm00080; https://onlinelibrary.wiley.com/doi/full-xml/10.1002/9781118960608.cbm00080

Abstract Hy.dro.ge.no.phi.la'li.a. N.L. masc. n. Hydrogenophilus type genus; suff. ‐ alia suffix to denote a class; N.L. neut. pl. n. Hydrogenophilalia the class of the Bacteria having 16S rRNA gene sequences and ribosomal protein amino acyl sequences related to those of the order Hydrogenophilales . Proteobacteria / Hydrogenophilalia Cells are rods and are motile by means of a single polar flagellum. Gram‐stain‐negative. Endospores, exospores, and cysts are not produced. Obligately respiratory metabolism using molecular oxygen or nitrate as terminal electron acceptors. Members of the class grow heterotrophically or facultatively autotrophically. Fatty acids, amino acids, aromatic compounds, and complex media support heterotrophic growth and molecular hydrogen acts as the electron donor for autotrophic growth. Thermophiles with optimal growth between 50 and 65°C. Cytochrome c oxidase‐positive, catalase‐positive. The major respiratory quinone is ubiquinone‐8 (UQ‐8). Dominant fatty acids are C 16:0 , C 19:0 cyclo , and C 17:0 cyclo —the high proportions of ω ‐cyclohexyl fatty acids being distinctive of the class versus the Betaproteobacteria . The class accommodates the single order Hydrogenophilales . Members of the class were isolated from waters and soils obtained from both natural ( viz . thermal springs in Iceland, the United States of America, India and Japan, and from the oilfields of Australia) as well as from anthropogenic environments (high‐temperature sludge digester in Portugal). DNA G + C content (mol%) : 58.6–65.0. Type order : Hydrogenophilales Garrity, Bell and Lilburn 2006, 2 VP (Effective publication: Garrity, Bell and Lilburn 2005, 763).