Effect of salinity on denitrification under limited single carbon source by Marinobacter sp. isolated from marine sediment.
Marinobacter comprises Gram-negative, aerobic, motile, and rod-shaped bacteria within the gamma-subclass of the Proteobacteria and is known to be halophilic or halotolerant, heterotrophic neutrophile. Two strains classified as belonging to Marinobacter, named PAD-2 and SeT-1, were isolated from marine sediment. The most closely related species of PAD-2 and SeT-1 are M. alkaliphilus and M. guinea, respectively. The strain PAD-2 exhibited remarkably higher denitrification at concentrations of 0.5 to 1 M NaCl (3-6% w/w) than at other salinities (2 and 3 M NaCl, 12-18% w/w), and optimal denitrification was observed in media with 0.5 M NaCl. The effect of pH on denitrification by strain PAD-2 was also examined, and the optimum denitrification occurred at neutral pH rather than under alkaline conditions. Overall, strain PAD-2 appears to be a novel halotolerant species belonging to the genus Marinobacter that shares many characteristics, such as substrate utilization profile and optimum NaCl concentration for growth with M. alkaliphilus.
Nakano
Miyo
M
Marine Microbiology, Faculty of Bioresources, Mie University, Kurimamachiya-cho, Tsu, Mie, Japan.
Inagaki
Tadashi
T
Okunishi
Suguru
S
Tanaka
Reiji
R
Maeda
Hiroto
H
D002244:Carbon / Q000378:metabolism*; D016000:Cluster Analysis; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D019015:Geologic Sediments / Q000382:microbiology*; D053520:Marinobacter / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D008969:Molecular Sequence Data; D009566:Nitrates / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D054712:Salinity; D017422:Sequence Analysis, DNA
D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009566:Nitrates; D009573:Nitrites; D012336:RNA, Ribosomal, 16S; D002244:Carbon; D009584:Nitrogen