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Gracilicutes (Latin: ''gracilis'', slender, and ''cutis'', skin, referring to the cell wall) is a controversial taxon in bacterial taxonomy. Traditionally gram staining results were most commonly used as a classification tool, consequently until the advent of molecular phylogeny, the Kingdom ''Prokaryotae'' (as the domain Bacteria was known then) was divided into four phyla,〔GIBBONS (N.E.) and MURRAY (R.G.E.): Proposals concerning the higher taxa of bacteria. International Journal of Systematic Bacteriology, 1978, 28, 1-6.〕 * ''Gracilicutes'' (gram-negative) * ''Firmacutes'' () (gram-positive, subsequently corrected to ''Firmicutes''〔MURRAY (R.G.E.): The higher taxa, or, a place for everything...? In: N.R. KRIEG and J.G. HOLT (ed.) Bergey's Manual of Systematic Bacteriology, vol. 1, The Williams & Wilkins Co., Baltimore, 1984, p. 31-34〕) * ''Mollicutes'' (gram variable, e.g. ''Mycoplasma'') * ''Mendocutes'' (uneven gram stain, "methanogenic bacteria" now known as methanogens and classed as ''Archaea'') This classification system was abandoned in favour of the three-domain system based on molecular phylogeny started by C. Woese. This taxon was revived in 2006 by Cavalier-Smith as an infrakindgom containing the phyla Spirochaetae, Sphingobacteria, Planctobacteria, and Proteobacteria. However, this taxon is not generally accepted and the three-domain system is followed. It is a gram-negative clade that branched off from other bacteria just before the evolutionary loss of the outer membrane or capsule, and just after the evolution of flagella.〔 ==Relationships== The following graph shows Cavalier-Smith's version of the tree of life, indicating the status of Gracilicutes. }} |label1= () Gracilicutes |label2= () |2= }} }} }}}}}}}}}} Legend: () Gram-negative with a peptidoglycan cell wall like Chlorosome. () Oxygenic Photosynthesis, (Omp85 ) and four new catalases. () Glycobacterial revolution: outer membrane with insertion of lipopolysaccharides, hopanoids, diaminopimelic acid, (ToIC ) and TonB. () Phycobilin chromophores. () Flagella. () Four sections: an amino acid in HSP60 and FtsZ and a domain in RNA polymerases β and σ. () Endospores. () Gram-positive Bacteria: hypertrophy of the wall peptidoglycan, (sortasa ) enzyme and a loss of the outer membrane. () Glycerol 1-P dehydrogenase. () Proteasome and phosphatidylinositol. () Neomura revolution: Replacement of peptidoglycan by glycoproteins and lipoproteins. () Reverse DNA gyrase and ether lipid isoprenoids. () Phagocytosis. 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「Gracilicutes」の詳細全文を読む スポンサード リンク
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