Zobellella iuensis sp. nov., an aerobic denitrifying bacterium isolated from activated sludge
Journal
International Journal of Systematic and Evolutionary Microbiology
Journal Volume
72
Journal Issue
11
Date Issued
2022-01-01
Author(s)
Abstract
An aerobic denitrifying bacterium, designated as strain CPY4T, was isolated from activated sludge treating urban sewage under alternating aerobic/anaerobic conditions by an enrichment culture technique. Cells of strain CPY4T were Gram-stain-negative, aerobic, long rod-shaped, motile by means of single polar flagellum and capable of aerobic denitrification with citrate as the carbon source. Growth of strain CPY4T was observed at 10–45 °C (optimum, 30–35 °C), at pH 6.0–10.5 (optimum, pH 8.0–8.5) and in 0–5 % NaCl (optimum, 0–3 %; w/v). The 16S rRNA gene sequence of strain CPY4T showed the highest similarity to Zobel-lella denitrificans ZD1T (97.9 %), followed by Zobellella endophytica 59N8T (97.6 %), Zobellella aerophila JC2671T (97.2 %), Zobellella taiwanensis ZT1T (97.1 %) and Zobellella maritima 102-Py4T (96.3 %). Genome comparisons between CPY4T and other Zobel-lella species showed highest digital DNA–DNA hybridization with Z. denitrificans ZD1T (43.8 %) and highest average nucleotide identity (ANIb and ANIm) of genome nucleotide sequences with Z. denitrificans ZD1T(90.7 and 92 %, respectively). Phylogenetic analysis revealed that strain CPY4T fell within the clade comprising the type strains of Zobellella species and formed a phyletic line with them, which was distinct from other members of the family Aeromonadaceae. The sole respiratory ubiquinone was quinone 8. The predominant fatty acids (>10 % of the total fatty acids) of strain CPY4T were summed feature 8 (C18: 1 ω6c and/ or C18: 1 ω7c), summed feature 3 (C16: 1 ω6c and/or C16: 1 ω7c) and C16: 0 . The genomic DNA G+C content was 62.7 mol %. In the polar lipid profile, diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl ethanolamine, phospholipids and aminolipids were the major compounds. Based on the genotypic and phenotypic data, strain CPY4T represents a novel species of the genus Zobellella, for which the name Zobellella iuensis sp. nov. is proposed. The type strain is CPY4T (=JCM 34456T=CGMCC 1.18722T).
Subjects
activated sludge | aerobic denitrification | new species | Zobellella
Publisher
MICROBIOLOGY SOC
Type
journal article