2.Screening and Identification of an Independent-glutamic Acid Strain Producing Poly (?-glutamic acid)
Qing-Shan SHI ; Cheng-Bin LI ; Chun-Hua WANG ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 1992;0(02):-
17 strains of bacterium that produced a large amount of ?-PGA when it was grown aerobically in a culture medium containing ammonium salt and sugar as sources of nitrogen and carbon respectively,were isolated from bean products.With the following identifications of colony morphology,physiological and biochemistry experiments,and genetics,the strain PGA-O-7 was classified as a Bacillus subtilis.The PGA production 2.8 (mg/mL) was obtained when it was grown in a medium containing 3% ammonium sulfate and 4% glucose at 30℃ for 72h with sharking.
3.Identification and Simulation Mutation of a High-productive Strain of Poly(?-glutamic acid) Independent of Glutamic Acid
Xiu-Lin SHU ; Qing-Shan SHI ; Jing FENG ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 1992;0(05):-
A high productive poly ?-glutamic acid(?-PGA) strain PGA-N in a culture medium containing no L-glutamine was isolated from fermentation products.With the following identifications of colony mor-phology,physiological and biochemistry experiments,and genetics,the strain PGA-N was classified as a Bacillus licheniformis.According to the product environment,the base culture medium having no L-glutamine was simulated.In order to enhance the production of the strain PGA-N,the fermentation condi-tions,such as carbon source,nitrogen source,were optimized and the ?-glutamic acid production reached 5.16 g/L after getting the optimum formulation of this culture medium.PGA-N was mutagenized with com-bination of NTG and UV.A mutant PGA-N-C10 was screened which PGA production was increased from 5.16 g/L to 8.82 g/L.The study also investigated the effects of agitation speed on the cell biomass,?-PGA production and the ?-PGA molecular weight.The ?-PGA yield of PGA-N-C10 was as high as 11.00 g/L when the agitation speed was 400 r/min.
4.Research Progress on the Polyphasic Taxonomy of Acetic Acid Bacteria
Jing FENG ; Qing-Shan SHI ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 2008;0(09):-
Acetic acid bacteria are Gram-negative,obligate aerobic bacteria that have the ability to incompletely oxidize alcohols or sugars to organic acids as end products. The taxonomy of acetic acid bacteria has undergone many changes in the last 30 years. The early classification systems for these bacteria were based on morphological and biochemical characteristics. Today,the acetic acid bacteria are classified as the consensus result of a polyphasic analysis,combining phenotypic,chemotaxonomic and genotypic data. This paper reviewed the polyphasic taxonomy of acetic acid bacteria,mainly introduced the current classification of acetic acid bacteria,then discussed the application of phenotypic,chemotaxonomic and genotypic method in the taxonomy of acetic acid bacteria.
5.Application of tri-operators breast blood oxygen imaging to diagnose breast cancer
Qing SHAO ; Xie HAN ; Kai XIA ; Ye LU ; Caijun LI ; Ying SU ; Xiaolan YOU ; Hailing SHAN ; Runlong ZOU
Journal of Endocrine Surgery 2009;3(5):313-315
Objective To use tri-operator breast blood oxygen imaging in diagnosis of early stage breast cancer.Methods To analysis and diagnosis eighty cases with the technology of breast blood oxygen imaging.Results The accurate rate of the diagnosis made by technology of breast blood oxygen imaging was 93.75%,the sensitivity of diagnosis was 90.63%,the specificity was 95.83%.Conclusions The technology of breast blood oxygen imaging without the radiation may be a better methods to diagnosis the breast diseases,which has the higher sensitivity than infrared rays examination on breast cancer diagnosis.
6.The Concentration and Variation of Airborne Microbe in Guangzhou City
You-Sheng OUYANG ; Xiao-Bao XIE ; Yi-Ben CHEN ; Xiao-Mo HUANG ; Hong PENG ; Qing-Shan SHI ;
Microbiology 1992;0(03):-
One year survey on the concentrations and monthly or seasonal variations of airborne microbe in Guangzhou city were analysed and studied with JWL-IIB airborne microbial sampler. The results showed that the yearly average airborne microbe content of outdoor was 2, 298 cfu/m3, and that of indoor was 1,792 cfu/m3 in Guangzhou city. The monthly variation range of outdoor airborne microbe was from 1,073 to 4,096 cfu/m3, the highest content was 4,096 cfu/m3 in March, and the lowest content was 1,073 cfu/m3 in October. The outdoor airborne bacteria and fungi counts were the highest in spring, next in summer, lower in winter and the lowest in autumn in the four seasons . The yearly average concentrations of outdoor airborne microbe at the Garbage compression station, the business walk street, the key traffic route, the residential area, the industrial district and the garden were 4, 573, 3, 835, 1, 580, 1,413, 1, 197 and 1, 187 cfu/m3respectively; and Ones of indoor at the key traffic route, the tourist three star-route hotel and the subway station were 2,511, 1,699and 1,167 cfu/m3 respectively . The study on airborne microbe can be used for the research of health prevention and environment control measures in Guangzhou .
7.Isolation and Identification of BLN-2 Producing Poly-?-Glutamic Acid and Studies on Its Solid-state Fermentation
Jing FENG ; Qing-Shan SHI ; Xiu-Lin SHU ; Xiao-Ping LIN ; You-Sheng OUYANG ; Yi-Ben CHEN ;
Microbiology 2008;0(09):-
A poly-?-glutamic acid producing strain--BLN-2, was isolated from the soybean products. According to the biochemical characteristics and 16S rRNA, the strain was identified as Bacillus subtilis. Using soybeans as culture, the solid-state fermentation conditions of BLN-2 have been studied. The results showed that the optimal carbon and nitrogen sources of BLN-2 were glucose, fructose, NaNO3 and KNO3, respectively. The orthrogonal experiments showed, when the final concentration of the fructose which was added to the soybean culture was 0.5%, the glucose, NaNO3 and KNO3 final concentraion were 2.0%, the production of ?-PGA was the highest--89.05 g/kg. It is 48.42% higher than other comparable soybean medium under the same conditions.
8.Construction and identification of a specific small interfering RNA expression vector of Caspase-12 in mouse hepatoma cell line
Lan-Yi LIN ; Qing XIE ; Hui WANG ; Shan JIANG ; Xia ZHOU ; Liu QIU ; Ye YUN ; Hong YU ; Qing GUO ; You-Xin JIN
Chinese Journal of Infectious Diseases 2000;0(02):-
Objective To construct a specific small interfering double-stranded RNA(siRNA) expression vector of Caspase-12 and to evaluate inhibitory effect of this siRNA on caspase-12 mRNA activity.Methods Three groups of siRNA targeting different gene sites of caspase-12 were designed and synthesized chemically.Mouse hepatoma cell line,Hepa1-6,was transfected with the siRNA by 24 h.Reverse transcription-polymerase chain reaction(RT-PCR)was performed to analyze the inhibi- tion of caspase-12.Then the most effective siRNA was selected and the two template sequences for the siRNA were inserted into pRNAT-H1.1Neo expression vector.The recombinant plasmid, referred to as pRNAT-casp12,was verified by PCR analysis and sequencing.The expression of caspase-12 at mRNA and protein level,after transfection with pRNAT-casp12 by 48 h and 72 h respectively,were analyzed by using real-time PCR and Western blotting.Results The chemically synthesized siRNA*1 and siRNA*3 could inhibit mouse hepatoma cell caspase-12 mRNA by 59.9% and 39.6%(P
9.Preparation and identification of hammerhead ribozyme in vitro against caspase-12 mRNA fragments.
Shan JIANG ; Qing XIE ; Wei ZHANG ; Xia-Qiu ZHOU ; Hong YU ; You-Xin JIN
Chinese Journal of Hepatology 2005;13(2):121-124
OBJECTIVETo design and synthesize ribozymes targeting 138 and 218 sites of the mRNA nucleotide of mouse caspase-12, a key intermedium of ER stress mediated apoptosis, and to identify their activities through in vitro transcription and cleavage.
METHODSThe mouse caspase-12 gene fragment was obtained by RT-PCR and cloned into the PGEM-T vector under the control of T7 RNA polymerase promoter. The transcription product of the target was labeled with a-32P UTP, while ribozymes were not labeled. Ribozyme and target RNA were incubated for 90 min at 37 degree C in a reaction buffer to perform the cleavage reaction.
RESULTSIt was found that under a condition of 37 degree C, pH 7.5 and with Mg2+ in a concentration of 10 mmol/L, Rz138 and Rz218 both cleaved targets at predicted sites, and the cleavage efficiency of Rz138 was 100%.
CONCLUSIONRz138 and Rz218 prepared in vitro possess the perfect specific catalytic cleavage activity. Rz138 has excellent cleavage efficiency. It may be a promising tool to prevent ER stress induced apoptosis through catalytic cleavage of caspase-12 mRNA in vivo. It also can be used to verify whether caspase-12 is necessary in ER stress induced apoptosis.
Animals ; Base Sequence ; Caspase 12 ; genetics ; Endoplasmic Reticulum ; metabolism ; Mice ; Mice, Inbred BALB C ; Molecular Sequence Data ; Oxidative Stress ; genetics ; RNA, Catalytic ; chemistry ; genetics ; RNA, Messenger ; genetics
10.Clone, expression and cleavage activity of anti-caspase-7 hammerhead ribozyme in vitro.
Wei ZHANG ; Qing XIE ; Xia-qiu ZHOU ; Shan JIANG ; You-xin JIN
Chinese Journal of Hepatology 2004;12(11):684-687
OBJECTIVETo design hammerhead ribozymes against mouse caspase-7 and to study their expression and cleavage activity in vitro.
METHODSThe secondary structures of ribozyme and caspase-7 genes were analyzed and simulated by computer. Ribozymes DNA sequences were synthesized by automatic synthetic apparatus. Caspase-7 DNA sequence was acquired by reverse transcription PCR. Ribozymes and caspase-7 DNA sequences were separately cloned into pBSKneo U6 and pGEM-T vectors. Ribozymes and caspase-7 mRNA were obtained by transcription in vitro, and ribozymes cleavage activity was identified by cleavage experiment in vitro.
RESULTSTwo ribozymes named Rz333 and Rz394 targeting 333 and 394 sites in caspase-7 mRNA were designed by computer software, and their DNA sequences were synthesized. The expression vector of caspase-7 and plasmids containing Rz333 and Rz394 were reconstructed successfully. Ribozymes and caspase-7 mRNA were expressed by in vitro transcription. In vitro cleavage experiments showed that Rz333 cleaved caspase-7 mRNA and produced 243nt and 744nt segments. The cleavage efficiency is 67.98%, while Rz394 cannot cleave caspase-7 mRNA.
CONCLUSIONSRz333 can site-specifically cleave caspase-7 mRNA.
Animals ; Base Sequence ; Caspase 7 ; Caspase Inhibitors ; Caspases ; genetics ; Cloning, Molecular ; Mice ; Mice, Inbred BALB C ; Molecular Sequence Data ; RNA, Catalytic ; biosynthesis ; genetics ; metabolism ; RNA, Messenger ; biosynthesis ; genetics