ABSTRACT
An ethanol-utilizing Fe(III)-reducing bacterial strain, OSK2A(T), was isolated from a lotus field in Aichi, Japan. Phylogenetic analysis of the 16S rRNA gene sequences of OSK2A(T) and related strains placed it within Geobacter sulfurreducens PCA(T). Strain OSK2A(T) was shown to be a Gram-negative, motile, rod-shaped bacterium, strictly anaerobic, 0.76-1.65 µm long and 0.28-0.45 µm wide. Its growth occurred at 20-40â, pH 6.0-8.1, and it tolerated up to 1% NaCl. The G+C content of the genomic DNA was 61.2 mol% and DNA-DNA hybridization value with Geobacter sulfurreducens PCA(T) was 60.7%. The major respiratory quinone was MK-8. The major fatty acids were 16ï¼1 ω7c, 16ï¼0, 14ï¼0, 15ï¼0 iso, 16ï¼1 ω5c, and 18ï¼1 ω7c. Strain OSK2A(T) could utilize H2, ethanol, acetate, lactate, pyruvate, and formate as substrates with Fe(III)-citrate as electron acceptor. Amorphous Fe(III) hydroxide, Fe(III)-NTA, fumarate, malate, and elemental sulfur were utilized as electron acceptors with either acetate or ethanol as substrates. Results obtained from physiological, DNA-DNA hybridization, and chemotaxonomic tests support genotypic and phenotypic differentiation of strain OSK2A(T) from its closest relative. The isolate is assigned as a novel subspecies with the name Geobacter sulfurreducens subsp. ethanolicus, subsp. nov. (type strain OSK2A(T)=DSMZ 26126(T)=JCM 18752(T)).
Subject(s)
Ethanol/metabolism , Ferric Compounds/metabolism , Geobacter/classification , Geobacter/isolation & purification , Soil Microbiology , Aerobiosis , Bacterial Typing Techniques , Base Composition , Cluster Analysis , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Fatty Acids/analysis , Geobacter/genetics , Geobacter/physiology , Hydrogen-Ion Concentration , Japan , Lotus/growth & development , Microscopy, Electron, Scanning , Molecular Sequence Data , Nucleic Acid Hybridization , Oxidation-Reduction , Phylogeny , Quinones/analysis , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Sodium Chloride/metabolism , TemperatureABSTRACT
A novel species of Fe(III)-reducing bacterium, designated strain OSK6(T), belonging to the genus Geobacter, was isolated from lotus field mud in Japan. Strain OSK6(T) was isolated using a solid medium containing acetate, Fe(III)-nitrilotriacetate (NTA) and gellan gum. The isolate is a strictly anaerobic, gram-negative, motile, straight rod-shaped bacterium, 0.6-1.9 µm long and 0.2-0.4 µm wide. The growth of the isolate occurred at 20-40 °C with optima of 30-37 °C and pH 6.5-7.5 in the presence of up to 0.5 g NaCl l(-1). The G+C content of the genomic DNA was determined by HPLC to be 59.7 mol%. The major respiratory quinone was MK-8. The major fatty acids were 16â:â1ω7c and 16â:â0. Strain OSK6(T) was able to grow with Fe(III)-NTA, ferric citrate, amorphous iron (III) hydroxide and nitrate, but not with fumarate, malate or sulfate as electron acceptors. Among examined substrates grown with Fe(III)-NTA, the isolate grew on acetate, lactate, pyruvate and succinate. Analysis of the near full-length 16S rRNA gene sequence revealed that strain OSK6(T) is closely related to Geobacter daltonii and Geobacter toluenoxydans with 95.6â% similarity to the type strains of these species. On the basis of phylogenetic analysis and physiological tests, strain OSK6(T) is described as a representative of a novel species, Geobacter luticola sp. nov.; the type strain is OSK6(T) (â=âDSM 24905(T)â=âJCM 17780(T)).
Subject(s)
Ferric Compounds/metabolism , Geobacter/classification , Geologic Sediments/microbiology , Lotus/microbiology , Phylogeny , Bacterial Typing Techniques , Base Composition , DNA, Bacterial/genetics , Fatty Acids/analysis , Geobacter/genetics , Geobacter/isolation & purification , Japan , Molecular Sequence Data , Nitrates/metabolism , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Vitamin K 2/analogs & derivatives , Vitamin K 2/analysisABSTRACT
We report a case of an individual with cervical spinal cord injury who showed a unique blood pressure response during passive standing and passive walking-like leg movement, i.e., hypertension with standing and hypotension with leg movement.
Subject(s)
Blood Pressure/physiology , Exercise Therapy , Quadriplegia/physiopathology , Quadriplegia/rehabilitation , Adult , Electromyography , Humans , Hypotension, Orthostatic/prevention & control , Lung/metabolism , Male , Motion Therapy, Continuous Passive , Oxygen Consumption/physiology , Posture/physiology , Respiratory Function Tests , Walking/physiologyABSTRACT
We examined ventilatory response during passive walking-like exercise in the standing posture in complete spinal cord-injured humans and found that ventilatory equivalent for O(2) uptake, which would be related to the sensation of breathlessness, was lower during passive exercise than during quiet standing.
