ABSTRACT
To investigate the superoxide dismutase in extremthermoacidal environment,a reliable three-dimensional molecular structure of the protein encoded by the sod gene from Thermoplasma acidophilum was built.Evolutionary trace analysis of this protein detected 11 trace residues.Among them,the residues of Ash39,Gly105 and Glu162 were randomly scattered throughout the mapped structure;the other residues were all distinctly clusteredin a subgroup near Fe atom binding site.From these results,this gene encoded a Fe-depending superoxide dismutase based on the modeled structure;moreover,the detected trace residues around Fe atom might be directly responsible for Febinding and catalytic function.
ABSTRACT
To investigate the superoxide dismutase in extremthermoacidal environment,a reliable three-dimensional molecular structure of the protein encoded by the sod gene from Thermoplasma acidophilum was built.Evolutionary trace analysis of this protein detected 11 trace residues.Among them,the residues of Ash39,Gly105 and Glu162 were randomly scattered throughout the mapped structure;the other residues were all distinctly clusteredin a subgroup near Fe atom binding site.From these results,this gene encoded a Fe-depending superoxide dismutase based on the modeled structure;moreover,the detected trace residues around Fe atom might be directly responsible for Febinding and catalytic function.
ABSTRACT
With reverse transcriptase PCR, the transcripton of copper homeostasis relative gene Afe0329 in Acidithiobacillus ferrooxians standard strain ATCC23270 was investigated. The further analysis of genes in this transcripton was analyzed employed by Vector NTI, Blast, TMHMM Server, PSORTb software and so on. From the DNA of different strains, the transcripton of Afe0329 was amplified using special primer pairs to identify the universality of it in the genome of A.ferrooxidans strains. The results showed that gene Afe0330 and Afe0331 were cotranscribed with Afe0329, and they were in a single transcripton. Gene Afe0329 was supported to express a P1b3-type ATPase which is a heavy metal ion pumping transmembrane protein, protein AFE0330 which expressed by gene Afe0330 was a cytoplasmic protein, no significant ho- mologous sequences of Afe0330 or Afe0331 had been obtained by Blast analysis. And the transcripton of Afe0329 was universal in genome of A. ferrooxidans strains.
ABSTRACT
Reverse transcriptase-PCR experiments suggest that the two clusters of genes potentially involved in the oxidation of reduced sulfur compounds are organized as operons in strain of the acidophilic, chemolithoautotrophic bacterium Acidithiobacillus ferrooxidans ATCC 23270, the two clusters of genes including such the ORF of putative sulfate-thiosulfate-molybdate binding proteins, the ORF of putative thiosulfate: quinone oxidoreductase and the ORF of the rhodanese-like protein (P21). Bioinformatic analyses have predicted the possible promoters sequences and the possible +1 start site of transcription for the doxDA operons.
ABSTRACT
To have a better understanding on the evolution of Metallosphaera sedula-mediated precipitation and the properties of the precipitate synthesized by this species，a newly identified extremely thermophilic strain (YN23) of Metallosphaera sedula was cultured in the medium containing Fe2+ as energy resouTce under optimal condidons (pH1.5，65℃,0.2g·1-1 yeast extract,30g·1-1 Fe2SO4·7H2O and 170rpm)．XRD，EDS，ETIR and SEM reveal the precipitate obtained from YN23-inoculated flasks to be a mixture of potassium jarosite and ammoniojarosite，with morphological features similar to the latter．Precipitation Was first detected once over 90％ of Fe2+ was oxidized at hour 25 with a peak pH value of 1.92，and was ended when precipitate reached the highest point of 7.9g·1-1 at hour 95 with the lowest pH value of 1.32 in solution．Microbial density underwent a rapid increase along with Fe2+ oxidation and a gradual decrease with precipitate piling up.
ABSTRACT
To have a better understanding on the evolution of Metallosphaera sedula-mediated precipitation and the properties of the precipitate synthesized by this species，a newly identified extremely thermophilic strain (YN23) of Metallosphaera sedula was cultured in the medium containing Fe2+ as energy resouTce under optimal condidons (pH1.5，65℃,0.2g·1-1 yeast extract,30g·1-1 Fe2SO4·7H2O and 170rpm)．XRD，EDS，ETIR and SEM reveal the precipitate obtained from YN23-inoculated flasks to be a mixture of potassium jarosite and ammoniojarosite，with morphological features similar to the latter．Precipitation Was first detected once over 90％ of Fe2+ was oxidized at hour 25 with a peak pH value of 1.92，and was ended when precipitate reached the highest point of 7.9g·1-1 at hour 95 with the lowest pH value of 1.32 in solution．Microbial density underwent a rapid increase along with Fe2+ oxidation and a gradual decrease with precipitate piling up.
ABSTRACT
Microalgae biodiesel can solve these problems currently of plants materials,such as:shortage of arable land,impact of climate change for production and to lead high crop prices and so on.Constructing "engineered microalgae" through transgenic technology,the microalgae have capacity of high growth,shorter periods of growth and several times higher oil production than terrestrial plants.Furthermore,sea water can be as its natural medium for industrial production.The advantages of microalgae biodiesel,current status and progress of researches on engineered microalgae as well as product technologies of microalgal biodiesel was introduced.
ABSTRACT
There are similarities between magnetotactic bacteria and Acidithiobacillus ferrooxidans (A. ferrooxidans) which isolated from Acid mine drainage(AMD). The weak magnetotaxis of some bioleaching bacteria isolated were found by microscope. A magnetophoresis apparatus was designed based on these weak magnetotaxis and be used to analysis the movement of these strains. The physiological properties of the anear magnetic field strain and removed magnetic field strain which isolated successfully by magnetophoresis apparatus have large difference. The nanometer magnetic particles was extract from the Acidithiobacillus ferrooxidans which purified by spread plate method from AMFS and its main elements are Fe and O by energy spectrum analysis. The results show that A. ferrooxidans have weak magnetotaxis and can be isolated by magnetophoresis. With the development of this new isolating method, the research of magnetotactic bacteria and bioleaching will get more benefit from it.