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HIGH SCHOOL

Biology

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Microbiology

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Introduction to Microbiology

Gram and Acid-Fast Staining Methods

Description

Gram and acid-fast staining methods help scientists tell bacteria apart by looking at their cell walls. These differential stains are important in microbiology because they support identification, diagnosis, and research. They use structural and chemical differences in bacterial cell walls to separate microorganisms into cle...

Transcript

差异染色根据细胞壁特性区分微生物,有助于细菌鉴定和分类。

革兰氏染色根据细菌在酒精脱色后保留结晶紫的能力将细菌分为革兰氏阳性或革兰氏阴性。

将微生物培养物的薄涂片铺在载玻片上,风干并热固定。

涂片用结晶紫染色,用水洗涤,用碘处理,形成结晶紫-碘络合物。

使用酒精使这些涂片脱色,直到径流澄清,然后用水冲洗。

革兰氏阳性菌由于其较厚的肽聚糖层而保留了紫色染色。

相比之下,革兰氏阴性菌会失去紫色污渍,因为酒精会破坏外膜并洗掉结晶紫碘复合物。

红黄素用于复染革兰氏阴性菌粉红色,而革兰氏阳性菌保持紫色。

抗酸染色可检测 分枝杆菌 种,其蜡质、富含分枝杆菌酸的细胞壁抵抗脱色。

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