Paracoccus hibisci sp. Nov., isolated from the rhizosphere of Hibiscus syriacus L. (Mugunghwa flower)

A Gram-stain-negative, aerobic, short-rod-shaped bacterium, motile by means of one flagellum (THG-T2.8T), was isolated from the rhizosphere of Mugunghwa flower. Growth occurred at 10–37 °C (optimum 28 °C), at pH 6–8 (optimum 7) and with 0–5%NaCl (optimum 1 %). The major quinone was ubiquinone-10 (Q-10). The major fatty acids were C_{10: 0} 3-OH, C_{16: 0}, C_{18: 0} and C_{18: 1}ω7c. The polar lipids were diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminolipid, two unknown phospholipids, one unknown glycolipid and one unidentified lipid. The DNA G+C content of strain THG-T2.8^T was 65.5 mol%. Based on 16S rRNA gene sequence analysis, the nearest phylogenetic neighbours of strain THG-T2.8^T were identified as Paracoccus tibetensis Tibet-S9a3^T (98.6 %), Paracoccus aestuarii B7^T (98.4 %), Paracoccus rhizosphaerae CC-CCM15-8^T (98.3 %) and Paracoccus beibuensis JLT1284^T (98.2 %). Levels of sequence similarity among strain THG-T2.8^T and other species of the genus Paracoccus were lower than 98.0 %. DNA–DNA hybridization values between strain THG-T2.8^T and P. tibetensis Tibet-S9A3T^T, P. aestuarii B7^T, P. rhizosphaerae CC-CCM15-8^T and P. beibuensis JLT1284^T were 36.5% (38.8 %, reciprocal analysis), 32.8% (34.8 %), 31.6% (33.8 %) and 15.3% (24.8 %), respectively. On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA–DNA hybridization data, strain THG-T2.8^T represents a novel species of the genus Paracoccus, for which the name Paracoccus hibisci sp. nov. is proposed. The type strain is THG-T2.8^T (=KACC 18932^T=CCTCC AB 2016181^T).