H enriciella

Abstract

Abstract Hen.ri.ci.el'la. N.L. fem. n. Henriciella named after A.T. Henrici, who first described the stalked bacteria genus Caulobacter . Proteobacteria / Alphaproteobacteria / Rhodobacterales / Hyphomonadaceae / Henriciella Cells are Gram‐negative, aerobic, non‐spore‐forming, rods. Some species are dimorphic having motile cells with a polar flagellum and cells possessing a stalk (prosthecum), ca. 0.1–0.2 µm in diameter, 0.5–0.7‐µm long, extending from one pole as a continuation of the long axis of the cell. Adhesive material is present at the distal end of the stalk. Occur singly. Multiplication by binary fission. Colonies are circular, convex, and colorless. Chemoorganotrophic, aerobes, can grow anaerobically, probably using amino acids as fermentable carbon sources. Cells can store carbon as poly‐β‐hydroxybutyrate and show activities of oxidase and catalase. Species do not reduce nitrate or produce indole. They have complex growth requirements and grow on peptone–yeast extract media with 30 g/l NaCl, with optimal growth between 10 and 50 g/l NaCl. No growth occurs with salt concentrations at or below 5 g/l. The temperature range for growth is 10–40°C, while 20–35°C is optimal. The major fatty acids are C 18:1 ω7 c and C 16:0 ; the major hydroxyl fatty acid is C 12:0 3 ‐OH; the major respiratory quinone is Q‐10. The main polar lipids are α‐ d ‐glucopyranosyl diacylglycerol, α‐ d ‐glucopyranuronosyl diacylglycerol, and phosphatidyl diacylglycerol. The currently described six species of the genus were all isolated from seawater. The genus Henriciella is classified within the family Hyphomonadaceae . DNA G + C content (mol%) : 58.9–62.2 (genome sequences). Type species : Henriciella marina Quan, Zeng, Xiao, Roh, Nam, Chang et al., 2009b, 2129 VP (Effectively published: Quan, Zeng, Xiao, Roh, Nam, Chang et al., 2009a, 160).