RESUMEN
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.
RESUMEN
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.
Asunto(s)
Acinetobacter , Genética , Adaptación Fisiológica , Proteínas Bacterianas , Genética , Metabolismo , Clonación Molecular , Frío , ADN Bacteriano , Genética , Electroforesis en Gel de Poliacrilamida , Vectores Genéticos , Genética , Modelos Genéticos , Plásmidos , Genética , Regiones Promotoras Genéticas , Genética , beta-Lactamasas , Genética , MetabolismoRESUMEN
<p><b>OBJECTIVE</b>Mercury (Hg), as one of the priority pollutants and also a hot topic of frontier environmental research in many countries, has been paid higher attention in the world since the middle of the last century. Guizhou Province (at N24 degrees 30'-29 degrees 13', E103 degrees 1'-109 degrees 30', 1 100 m above the sea level, with subtropical humid climate) in southwest China is an important mercury production center. It has been found that the mercury content in most media of aquatics, soil, atmosphere and in biomass of corns, plants and animals, is higher than the national standard. The present study aims to explore the influence of mercury pollution on the health of local citizens.</p><p><b>METHODS</b>The effect of rice from two mercury polluted experimental plots of Guizhou Province on the expression of c-jun mRNA in rat brain and c-jun protein in cortex, hippocampus and ependyma was observed using reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemical methods.</p><p><b>RESULTS</b>The results showed that the mercury polluted rice induced expression of c-jun mRNA and its protein significantly. Selenium can reduce Hg uptake, an antagonism between selenium and mercury on the expression of c-jun mRNA and c-jun protein.</p><p><b>CONCLUSION</b>c-jun participates in the toxicity process of brain injury by mercury polluted rice, the expression of c-jun mRNA in brain, and c-jun protein in rat cortex and hippocampus can predict neurotoxicity of mercury polluted rice. People should be advised to be cautious in eating any kind of Hg-polluted foods. To reveal the relationship between c-jun induction and apoptosis, further examinations are required.</p>
Asunto(s)
Animales , Ratas , Atmósfera , Secuencia de Bases , Biomasa , Encéfalo , Metabolismo , China , Contaminación de Alimentos , Genes jun , Genética , Inmunohistoquímica , Mercurio , Toxicidad , Oryza , Química , ARN Mensajero , Genética , Metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Contaminantes del Suelo , Toxicidad , Factores de TiempoRESUMEN
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.