Effects of Bupleurum chinense on the diversity of intestinal flora in depressed mice / 中国中药杂志

Bupleuri Radix, serving as the sovereign medicinal in many antidepressant compound preparations, has been proved effective in treating depression in mice, but its effect on the intestinal flora remains unclear. The present study aimed to investigate the effects of Bupleurum chinense(one of the original materials of Bupleuri Radix) on the behaviors and the diversity of intestinal flora of depressed mice. A depression mouse model was induced by repeated social defeat stress. Specifically, C57 BL/6 J male mice were exposed to the attack from the CD-1 mice. Then, C57 BL/6 J male mice were divided into a depression group and a B. chinense group, with normal saline and B. chinense administered(ig) respectively. Sucrose preference test and tail suspension test were conducted during and after the experiment respectively, to analyze the effects of B. chinense on the behaviors of the depressed mice. The feces were collected after the experiment. The V3-V4 16 S rDNA regions of intestinal flora of mice in each group were sequenced by Ion S5 TMXL for the analysis of the number of operational taxonomic units(OTUs), richness, alpha and beta diversity indexes, and differential phyla and genera. The results indicated that B. chinense could decrease depressive-like behaviors of mice, increase sucrose preference, and shorten the time of immobility in tail suspension test. After B. chinense intervention, the relative abundance of Firmicutes was significantly decreased, while that of Bacteroidetes was increased at the phylum level. At the genus level, the relative abundance of Lactobacillus and Lachnoclostridium decreased(P<0.05), while that of Bacteroides, Alistopes, etc. was elevated(P<0.05). The findings demonstrate that B. chinense can regulate the intestinal flora and improve the depressive-like behaviors of mice with depression.

Identification of a Thermoacidophilic Sulfolobus sp. Isolated from a Hot Spring in Tengchong Rehai / 微生物学通报

An extremely thermoacidophilic isolate K4-1 was obtained from an acidic hot spring in Teng- chong Rehai, Yunnan province. Morphology, growth characteristics, utilization of carbon compounds, en- ergy sources and 16S rRNA gene sequence of K4-1 were studied. Cells of K4-1 are irregular cocci with monotrichous flagella. The strain grew aerobically in either a lithotrophic or a heterotrophic mode. Growth on elemental sulfur occurred through oxidation of sulfur. It grew optimally at 75?C and pH 3.5. On the basis of 16S rRNA gene sequence similarity, strain K4-1 was shown to belong to genus Sulfolobus, being related to the type strains of genus Sulfolobus (86.6%~94.3% similarity), and being most closely related to strain Sulfolobus tengchongensis RT8-4 (98.9% similarity). The GenBank accession number of strain K4-1 16S rRNA gene sequence is EU729124.

Construction of promoter probe vector for a cold-adapted bacterium, Acinetobacter sp. DWC6 / 生物工程学报

In order to build a protein expression system in a cold-adapted bacterium Acinetobacter sp. DWC6, a promoter probe vector was constructed based on the plasmid pBR322. A fragment containing the promoter of the beta-lactamase gene (the ampicillin resistance gene) in pBR322 was eliminated and replaced by a fragment comprizing a kanamycin resistance gene amplified from pJRD215. DNA fragment harboring in the Acinetobacter species specific ori was also inserted into the plasmid pBR322 to construct a promoter probe vector named pBAP1, which could replicate both in E. coli and in Acinetobacter sp. DWC6. The promoter selection library was constructed by randomly inserting genomic DNA fragment of Acinetobacter sp. DWC6 at upstream of reported gene, and target promoters were screened from genomic library on ampicillin selection plates. The function of pBAP1 and isolated promoters were determined by detection of the ampicillin sensitivity and the expression level of beta-lactamase in the host cell.

Isolation and 16S rRNA Gene Sequence Analysis of a Thermotolerant Halophilic Bacterium / 微生物学通报

A strain of thermotolerant halophilic bacteria YJ0238 was isolated from the salt well at 47℃ in the Kangning countryside where was located at the side of Lancang River in the Tibet Autonomous Region. Some physiological and biochemical properties were characterized.16S rRNA gene sequence of YJ0238 was amplified by PCR,and its nucleotide sequence was determined. Based on it’s physiological and biochemical properties,homology and phylogenetic analysis of 16S rRNA gene sequence,strain YJ0238 was identified as a subspecies of the species Idiomarina zobellii. The GenBank accession number of the 16S rRNA gene sequence of strain YJ0238 is EF693953. Until now,there were few reports on the study of high-temperature and high-salt microbial in domestics. The results of this study will provide research material and information for further studies in this area.