Metals tolerance in moderately thermophilic isolates from a spent copper sulfide heap, closely related to Acidithiobacillus caldus, Acidimicrobium ferrooxidans and Sulfobacillus thermosulfidooxidans

2008 ◽  
Vol 36 (3) ◽  
pp. 461-465 ◽  
Author(s):  
E. L. J. Watkin ◽  
S. E. Keeling ◽  
F. A. Perrot ◽  
D. W. Shiers ◽  
M.-L. Palmer ◽  
...  
2018 ◽  
Vol 777 ◽  
pp. 277-281
Author(s):  
He Shang ◽  
Biao Wu ◽  
Jian Kang Wen ◽  
Xing Lan Cui

High-throughput sequencing technology also known as "next generation" sequencing technology, compared with the traditional sequencing method has the characteristics of fast speed, high flux, low cost. In recent years the technology in the detection of microbial diversity has been fully applied. In this study, the microbial community of ore heap in different area and different depth was studied by using this method. The results showed the bio - heap leaching of low - grade secondary copper sulfide ore in Zijinshan from China could effectively recover the copper in the ore. The number of microorganisms in the center was significantly larger than that on the edge of ore heap, and as the depth increases in the heap, the number of microorganisms decreases. The dominant bacteria in the ore heap center was Acidithiobacillus ferrooxidans, in addition there were also some Sulfobacillus thermosulfidooxidans, Ferroplasma cupricumulans, Acidithiobacillus caldus and a small amount of Leptospirillum ferriphilum in the center of the ore heap. Unlike the ore heap center, Sulfobacillus thermosulfidooxidans was the main species on the edge of the ore heap, moreover Acidithiobacillus ferrooxidans, Ferroplasma cupricumulans, Acidithiobacillus caldus and a small amount of Leptospirillum ferriphilum were found on the edge of the ore heap. In addition, some heterotrophic bacteria such as Pseudomonas, Serratia, Sediminibacterium, Stenotrophomonas, Brevundimonas and Variovorax were found both in the center and the edge of the sample, these heterotrophic bacteria may be beneficial for the leaching of valuable metals.


Microbiology ◽  
2006 ◽  
Vol 152 (12) ◽  
pp. 3551-3560 ◽  
Author(s):  
Andre A. Kotze ◽  
I. Marla Tuffin ◽  
Shelly M. Deane ◽  
Douglas E. Rawlings

All strains of the moderately thermophilic, acidophilic, sulphur-oxidizing bacterium Acidithiobacillus caldus that have been tested contain a set of chromosomal arsenic resistance genes. Highly arsenic-resistant strains isolated from commercial arsenopyrite bio-oxidation tanks contain additional transposon-located (TnAtcArs) arsenic resistance genes. The chromosomal At. caldus ars genes were cloned and found to consist of arsR and arsC genes transcribed in one direction, and arsB in the opposite direction. The arsRC genes were co-transcribed with ORF1, and arsB with ORF5 in both At. caldus and Escherichia coli, although deletion of ORFs 1 and 5 did not appear to affect resistance to arsenate or arsenite in E. coli. ORFs 1 and 5 have not previously been reported as part of the ars operons, and had high amino acid identity to hypothetical proteins from Polaromonas naphthalenivorus (76 %) and Legionella pneumophila (60 %), respectively. Reporter-gene studies showed that the arsenic operon of transposon origin (TnAtcArs) was expressed at a higher level, and was less tightly regulated in E. coli than were the At. caldus ars genes of chromosomal origin. Plasmid pSa-mediated conjugal transfer of TnAtcArs from E. coli to At. caldus strains lacking the transposon was successful, and resulted in greatly increased levels of resistance to arsenite.


2012 ◽  
Vol 62 ◽  
pp. 48-55 ◽  
Author(s):  
Tácia C. Veloso ◽  
Lázaro C. Sicupira ◽  
Isabel C.B. Rodrigues ◽  
Larissa A.M. Silva ◽  
Versiane A. Leão

2008 ◽  
Vol 74 (18) ◽  
pp. 5686-5694 ◽  
Author(s):  
Leonardo J. van Zyl ◽  
Jolanda M. van Munster ◽  
Douglas E. Rawlings

ABSTRACT Acidithiobacillus caldus is a moderately thermophilic, acidophilic bacterium that has been reported to be the dominant sulfur oxidizer in stirred-tank processes used to treat gold-bearing arsenopyrite ores. It is also widely distributed in heap reactors used for the extraction of metals from ores. Not only are these bacteria commercially important, they have an interesting physiology, the study of which has been restricted by the nonavailability of defined mutants. A recently reported conjugation system based on the broad-host-range IncW plasmids pSa and R388 was used to transfer mobilizable narrow-host-range suicide plasmid vectors containing inactivated and partially deleted chromosomal genes from Escherichia coli to A. caldus. Through the dual use of a selectable kanamycin resistance gene and a hybridization probe made from a deleted portion of the target chromosomal gene, single- and double-recombinant mutants of A. caldus were isolated. The functionality of the gene inactivation system was shown by the construction of A. caldus arsB and tetH mutants, and the effects of these mutations on cell growth in the presence of arsenic and by means of tetrathionate oxidation were demonstrated.


Extremophiles ◽  
2001 ◽  
Vol 5 (4) ◽  
pp. 247-255 ◽  
Author(s):  
Mark Dopson ◽  
Börje Lindström ◽  
Kevin Hallberg

2017 ◽  
Vol 38 (5) ◽  
pp. 292-297 ◽  
Author(s):  
Mohammad Ranjbar ◽  
Mohammad Hasan Fazaelipoor ◽  
Mahin Schaffie ◽  
Zahra Manafi ◽  
Mohammad Ranjbar Hamghavandi

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