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: '' Note: The word "halobacterium" is also the singular form of the word "halobacteria".'' In taxonomy, ''Halobacterium'' is a genus of the Halobacteriaceae.〔See the NCBI (webpage on Halobacterium ). Data extracted from the (【引用サイトリンク】 title=NCBI taxonomy resources )〕 The genus ''Halobacterium'' ("salt" or "ocean bacterium") consists of several species of archaea with an aerobic metabolism which require an environment with a high concentration of salt; many of their proteins will not function in low-salt environments. They grow on amino acids in their aerobic conditions. Their cell walls are also quite different from those of bacteria, as ordinary lipoprotein membranes fail in high salt concentrations. In shape, they may be either rods or cocci, and in color, either red or purple. They reproduce using binary fission (by constriction), and are motile. ''Halobacterium'' grows best in a 42 °C environment. The genome of an unspecified ''Halobacterium'' species has been sequenced and comprises 2,571,010 bp (base pairs) of DNA compiled into three circular strands: one large chromosome with 2,014,239 bp, and two smaller ones with 191,346 and 365,425 bp. This species, called ''Halobacterium'' sp. NRC-1, has been extensively used for post-genomic analysis. ''Halobacterium'' species can be found in the Great Salt Lake, the Dead Sea, Lake Magadi, and any other waters with high salt concentration. Purple ''Halobacterium'' species owe their color to bacteriorhodopsin, a light-sensitive protein which provides chemical energy for the cell by using sunlight to pump protons out of the cell. The resulting proton gradient across the cell membrane is used to drive the synthesis of the energy carrier ATP. Thus, when these protons flow back in, they are used in the synthesis of ATP (this proton flow can be emulated with a decrease in pH outside the cell, causing a flow of H+ ions). The bacteriorhodopsin protein is chemically very similar to the light-detecting pigment rhodopsin, found in the vertebrate retina. ==Species of ''Halobacterium''== * ''Halobacterium cutirubrum'' > ''Halobacterium salinarum'' * ''Halobacterium denitrificans'' > ''Haloferax denitrificans'' * ''Halobacterium distributum'' > ''Halorubrum distributum'' * ''Halobacterium halobium'' > ''Halobacterium salinarum'' * ''Halobacterium jilantaiense'' * ''Halobacterium lacusprofundi'' > ''Halorubrum lacusprofundi'' * ''Halobacterium mediterranei'' > ''Haloferax mediterranei'' * ''Halobacterium noricense'' * ''Halobacterium pharaonis'' > ''Natronomonas pharaonis'' * ''Halobacterium piscisalsi'' * ''Halobacterium saccharovorum'' > ''Halorubrum saccharovoru'' * ''Halobacterium salinarum'' * ''Halobacterium sodomense'' > ''Halorubrum sodomense'' * ''Halobacterium trapanicum'' > ''Halorubrum trapanicum'' * ''Halobacterium vallismortis'' > ''Haloarcula vallismortis'' * ''Halobacterium volcanii'' > ''Halobacterium volcanii'' 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「halobacterium」の詳細全文を読む スポンサード リンク
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