Gemmobacter caeruleus sp. nov., a novel species originating from lake sediment.

An aerobic, Gram-stain-negative, non-spore-forming and rod-shaped bacterial strain, designated N8T, was isolated from the interfacial sediment of Taihu Lake in PR China. The strain formed white to blue colonies on R2A agar. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain N8T represented a member of the genus Gemmobacter and was most closely related to Gemmobacter aquaticus A1-9T (97.97 %). The average nucleotide identity and digital DNA-DNAhybridization values between strain N8T and G. aquaticus A1-9T based on their whole genomes were 78.8 and 21.7 %, respectively. Q-10 was the main predominant ubiquinone. The major fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C18 : 0 and C16 : 0. The G+C content of the genomic DNA was 66.1 mol%. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, one unidentified phospholipid, two unidentified glycolipids and two unidentified lipids. Based on its physiological, biochemical and chemotaxonomic characteristics, strain N8T represents a novel species of the genus Gemmobacter, for which the name Gemmobacter caeruleus sp. nov. is proposed. The type strain is N8T=(KACC 21307T=MCCC 1K04036T).

[Design of a hollow-fiber bioreactor and perfusion study in vitro].

This article presents the design of a bioreactor using hollow fiber membrane and, isolated hepatocytes of suckling pigs, and the experimental study of its efficacy in vitro. Liver cells were harvested from suckling pigs with collagenase perfusion in situ, and parenchymal and non-parenchymal hepatocytes were cocultured in a hollow fiber module which was rotated sporadically. Bioartificial liver(BAL) was developed using this bioreactor,and the BAL was perfused with ascites of patients suffering from liver cirrhosis. The yield of viable hepatocytes was (6.29 +/- 0.37) x 10(8) cells, and cell viability was greater than 84%. Hepatocytes aggregated to multi-cells spheroids after being rotated every thirty minutes for three hours. The hepatocytes in the bioreactor could synthesize urea. Total billirubin was decreased, and AST was significantly increased in the group of bioreactor, as compared with that in the control group. Glucose decreased in the group of bioreactor,whereas there was no significant descent in the control group; and the difference between the two groups was significant. The above results demonstrate that this bioreactor is effective for decreasing total bilirubin and glucose.