出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2013/01/20 16:23:11」(JST)
Corynebacterium diphtheriae is a pathogenic bacterium that causes diphtheria. It is also known as the Klebs-Löffler bacillus, because it was discovered in 1884 by German bacteriologists Edwin Klebs (1834 – 1912) and Friedrich Löffler (1852 – 1915).
Contents
|
Four subspecies are recognized: C. diphtheriae mitis, C. diphtheriae intermedius, C. diphtheriae gravis, and C. diphtheriae belfanti. The four subspecies differ slightly in their colonial morphology and biochemical properties, such as the ability to metabolize certain nutrients, but all may be toxigenic (and therefore cause diphtheria) or non-toxigenic. Corynebacterium diphtheriae produces Diphtheria toxin which alters protein function in the host by inactivating elongation factor (EF-2). This causes pharyngitis and 'pseudomembrane' in the throat. The diphtheria toxin gene is encoded by a bacteriophage found in toxigenic strains, integrated into the bacterial chromosome.
In order to accurately identify C. diphtheriae, a Gram stain is performed to show gram-positive, highly pleomorphic organisms with no particular arrangement. Special stains like Alberts's stain and Ponder's stain are used to demonstrate the metachromatic granules formed in the polar regions. The granules are called as polar granules, Babes Ernst Granules, Volutin, etc.). An enrichment medium, such as Löffler's medium, is used to preferentially grow C. diptheriae. After that, use a differential plate known as tellurite agar, which allows all Corynebacteria (including C. diphtheriae) to reduce tellurite to metallic tellurium. The tellurite reduction is colormetrically indicated by brown colonies for most Cornyebacteria species or by a black halo around the C. diphtheriae colonies.
A low concentration of iron is required in the medium for toxin production. At high iron concentrations, iron molecules bind to an aporepressor on the beta bacteriophage, which carries the Tox gene. When bound to iron, the aporepressor shuts down toxin production.[1] Elek's test for toxogenecity is used to determine whether the organism is able to produce the diphtheria toxin or not.
The bacterium is sensitive to the majority of antibiotics, such as the penicillins, ampicillin, cephalosporins, quinolones, chloramphenicol, tetracyclines, cefuroxime and trimethoprim.
|
全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.
リンク元 | 「細菌」「ワクチン」「ジフテリア」「急性尿細管間質性腎炎」「ナイセル染色」 |
関連記事 | 「diphtheriae」「Corynebacterium」 |
病原体 | 感染症 | ワクチン | 学校伝染病 | ワクチンの形状 | 潜伏期間 | 季節性 | 年齢 | 出席停止解除条件 | |
ジフテリア菌 | Corynebacterium diphtheriae | ジフテリア | ジフテリア,破傷風,百目咳混合ワクチン | トキソイド | |||||
百日咳菌 | Bordetella pertussis | 百日咳 | ○ | 不活化 | 6~14 | 咳の消失 | |||
結核菌 | Mycobacterium tuberculosis | 結核 | BCG | ○ | 不活化 | 伝染のおそれが無くなるまで | |||
ポリオウイルス | poliovirus | ポリオ | ポリオワクチン(経口) | 生 | |||||
麻疹ウイルス | measles virus | 麻疹 | 麻疹・風疹混合ワクチン | ○ | 生 | 10~12 | 0~2 | 解熱後3日 | |
風疹ウイルス | rubella virus | 風疹 | ○ | 生 | 18 | 春~初夏 | 4~9 | 発疹消失 | |
日本脳炎ウイルス | Japanese encephalitis virus | 日本脳炎 | 日本脳炎ワクチン | 不活化 | |||||
インフルエンザウイルス | influenza virus | インフルエンザ | インフルエンザワクチン | ○ | 不活化 | 1~5 | 冬期 | 解熱後2日 | |
インフルエンザ菌 | Haemophilus influenzae | 化膿性髄膜炎など | Hibワクチン | ||||||
肺炎球菌 | Streptococcus pneumoniae | ||||||||
水痘・帯状疱疹ウイルス | varicella zoster virus | 水痘 | ○ | 生 | 11~21 | 冬(12, 1) | 5~9 | 発疹の痂皮化 | |
ムンプスウイルス | mumps virus | 流行性耳下腺炎 | ○ | 生 | 18~21 | 耳下腺腫脹消失 | |||
B型肝炎ウイルス | hepatitis B virus | B型肝炎 | 成分 | 60~160 | |||||
A型肝炎ウイルス | hepatitis A virus | A型肝炎 | 不活化 | 15~40 | |||||
狂犬病ウイルス | rabies virus | 狂犬病 | 不活化 | ||||||
アデノウイルス | adenovirus | 咽頭結膜熱 | ○ | ||||||
黄熱病ウイルス | yellow fever virus | 黄熱病 | 生 |
.