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''Candida'' is a genus of yeasts and is the most common cause of fungal infections worldwide.〔Manolakaki, D., Velmahos, G., Kourkoumpetis, T., Chang, Y., Alam, H. B., De Moya, M. M., & Mylonakis, E. (2010). Candida infection and colonization among trauma patients. Virulence, 1(5), 367-375.〕 Many species are harmless commensals or endosymbionts of hosts including humans; however, when mucosal barriers are disrupted or the immune system is compromised they can invade and cause disease.〔Kourkoumpetis, Themistoklis K., et al. "The effect of cumulative length of hospital stay on the antifungal resistance of Candida strains isolated from critically ill surgical patients." Mycopathologia 171.2 (2011): 85-91.〕 ''Candida albicans'' is the most commonly isolated species, and can cause infections (candidiasis or thrush) in humans and other animals. In winemaking, some species of ''Candida'' can potentially spoil wines.〔K. Fugelsang, C. Edwards ''Wine Microbiology'' Second Edition, pp. 3–28 Springer Science and Business Media , New York (2010) ISBN 0387333495〕 Many species are found in gut flora, including ''C. albicans'' in mammalian hosts, whereas others live as endosymbionts in insect hosts.〔Spanakis, Elias K., et al. "Statin Therapy and Decreased Incidence of Positive< i> Candida Systemic infections of the bloodstream and major organs (candidemia or invasive candidiasis), particularly in immunocompromised patients, affect over 90,000 people a year in the U.S.〔 The DNA of several ''Candida'' species has been sequenced.〔 Antibiotics promote yeast infections, including gastrointestinal ''Candida'' overgrowth, and penetration of the GI mucosa.〔Kennedy, MJ et al. "Mechanisms of association of Candida albicans with intestinal mucosa", Med Microbiol, volume-24, 333-341, 1987〕 While women are more susceptible to genital yeast infections, men can also be infected. Certain factors, such as prolonged antibiotic use, increase the risk for both men and women. People with diabetes or impaired immune systems, such as those with HIV, are more susceptible to yeast infections.〔(【引用サイトリンク】title=Yeast Infections: MedlinePlus )〕 ''Candida antarctica'' is a source of industrially important lipases. ==Biology== Grown in the laboratory, ''Candida'' appears as large, round, white or cream (''albicans'' is from Latin meaning 'whitish') colonies with a yeasty odor on agar plates at room temperature. ''C. albicans'' ferments glucose and maltose to acid and gas, sucrose to acid, and does not ferment lactose, which help to distinguish it from other ''Candida'' species. Many species of ''Candida'' use a non-standard genetic code in the translation of their nuclear genes into the amino acid sequences of polypeptides.〔(【引用サイトリンク】url=http://www.candidagenome.org/help/code_tables.shtml )〕 The difference in the genetic code between species possessing the alternative code is that the codon CUG (normally encoding the amino acid leucine) is translated by the yeast as a different amino acid, serine. The alternative translation of the CUG codon in these species is due to a novel nucleic acid sequence in the serine-tRNA (ser-tRNACAG), which has a guanosine located at position 33, 5' to the anticodon. In all other tRNAs , this position is normally is occupied by a pyrimidine (often uridine). This genetic code change is the only such known alteration in cytoplasmic mRNA, in both the prokaryotes, and the eukaryotes, involving the reassignment of a sense codon. This novel genetic code may be a mechanism for more rapid adaptation to the organism's environment, as well as playing an important role in the evolution of the genus ''Candida'' by creating genetic barriers that encouraged speciation〔 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「Candida (fungus)」の詳細全文を読む スポンサード リンク
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