粘液层和胶囊之间的差异

关键区别 - 粘液Layervs Capsule

Bacteria areprokaryoticsingle-cell microorganisms. They have different structures within the单细胞simple body structure. Most bacteria are surrounded by a thickcell wall。有些拥有一个额外的封面，称为信封。除细胞壁外，某些细菌含有外部结构。在外部结构中，糖脂是一个重要的结构，其中包括胶囊和粘液层。糖脂避免了细菌细胞phagocytosis, and it helps the formation of biofilms.黏液layer is an unorganized, loosely adhered thin glycocalyx that protects bacterial cells from drying that traps nutrients and aids in biofilm formation.Capsule is a highly organized, tightly bound thick glycocalyx that helps bacteria in avoiding the phagocytosis.This is thekey differencebetween slime layer and capsule.

内容

1.Overview and Key Difference
2.What is Slime Layer
3.What is Capsule
4.相似性粘液层和胶囊
5.Side by Side Comparison – Slime Layer vs Capsule in Tabular Form
6.概括

What is Slime Layer?

黏液layer is an unorganized loosely bound gelatinous extracellular layer of bacteria. When the glycocalyx of bacteria is thin and less discrete, it is known as a slime layer. Slime layer mainly protects bacteria from dehydration and antimicrobial agents and loss of nutrients. And also slime layer helps bacteria to form biofilms.

黏液layer is composed mostly of exopolysaccharides,glycoproteins和糖脂。粘液层由于其对细胞壁的粘附性松动而很容易被洗掉。

What is Capsule?

胶囊是某些细菌拥有的外部结构之一。胶囊由多糖聚合物制成。胶囊是一种有组织的结构，与粘液层不同，很难洗掉。胶囊围绕细菌的细胞包膜，并紧密结合到细胞包膜。胶囊厚，它有助于细菌避免吞噬作用。胶囊本质上是亲水性的，因此可以防止细菌脱水。

胶囊的产生是遗传控制的，并经过环境修饰。胶囊在不同细菌菌株之间具有广泛的密度，厚度和粘合性，并且可能由细胞膜产生。胶囊具有不同的化学成分，取决于物种。它们可能包括葡萄糖聚合物，复杂的多糖，氨基糖，糖酸，polypeptides单独或组合。

Capsule is considered as a毒力factor of bacteria due to its ability to enhance the escaping from the host defence mechanisms and causing the diseases.Straphylococcus aureus是一种抗嗜中性粒细胞吞噬作用的细菌物种。胶囊Streptococcus pneumoniaeis the key factor that causes肺炎。It is observed that the loss of capsule decreases virulence of bacteria.

Capsules have several functions. They often mediate adherence of cells to surfaces. Capsules also protect bacterial cells from engulfment by predatory protozoa orwhite blood cellsor from attack by antimicrobial agents. Sometimes capsules become reservoirs of carbohydrates when bacteria are fed with sugars. Another important characteristic of capsules is the ability to block some steps of the phagocytosis process and thereby prevent bacterial cells from being engulfed or destroyed by phagocytes.

可以通过显微镜下的印度墨水通过负染色技术来观察胶囊。胶囊将显示为细菌细胞周围的清晰光晕。封闭细菌的一些例子是果蝇，克雷伯氏菌肺炎，肺炎链球菌，灌注梭状芽胞杆菌。

What are the Similarities Between Slime Layer and Capsule?

• Both slime layer and capsule are components of the bacterial glycocalyx.
• 粘液层和胶囊都是细菌的毒力因子。
• Both slime layer and capsule are protective covers that aid bacteria.
• Both slime layer and capsule are located outside the cell envelope or cell wall.
• Both slime layer and capsule are not essential for the cell viability.
• Capsule and slime layer are mainly composed of polysaccharides.

粘液层和胶囊有什么区别？

黏液Layer vs Capsule
黏液Layer is an unorganized, loosely adhered extracellular polysaccharide layer surrounding the bacterial cell wall or envelope.	Capsule is an organized, well defined, condensed extracellular layer that is tightly bound to the cell envelope of bacteria.
功能
粘液层帮助细菌粘附在表面，抗菌剂，形成生物膜，保护细菌免受壁降解酶和噬菌体的影响。	胶囊的功能是预防细菌细胞的干燥和干燥，免受损伤和温度的保护，支撑对表面的附着，抵抗吞噬作用，预防噬菌体附着，供应营养素，并排斥其他细菌物种。
Organization
粘液层是一个无组织的层。	Capsule is an organized layer.
Thickness
粘液层是薄层。	胶囊是厚，密集的层。
Adherence to Cell Wall
粘液层松散地粘附在细胞壁上。	Capsule is firmly attached to the cell wall.
Pathogenic Factor
黏液Layer helps bacteria in gliding and protects them from antimicrobials.	Capsule resists phagocytosis.
Rigidity
黏液Layer is less rigid.	胶囊是刚性的。
Ability to Wash Off
黏液Layer is easily removable.	Capsule is hard to wash off.

概括–黏液Layervs Capsule

一些细菌在细胞壁外具有额外的层，称为糖脂。糖脂由细胞外材料制成。它可以保护细菌免受外部条件的侵害，并遵守表面。糖脂有两种形式；粘液层或胶囊。粘液层是与细菌细胞壁松散相关的细胞外层。这是一个不太离散的层，很容易被洗掉。胶囊紧密连接到细胞壁，是一个厚的离散层。胶囊不能轻易从细菌中除去。粘液层和胶囊都可以帮助细菌从干燥和抗菌剂中。 Most of the encapsulated bacteria are pathogenic, and they avoid from phagocytosis due to their capsules. This is the difference between slime layer and capsule.

Reference:

1.“Bacterial Capsule: structure, function and examples of Capsulated bacteria -.” – A Complete notes for Students, 23 July 2017.Available here
2. Rogers，Kara和Robert J. Kadner。“细菌。”2018年2月22日，英国百科全书，英国百科全书。Available here

Image Courtesy:

1.’Bacteria Capsules and Slime Layers’By Carlahayden11 – Own work,(CC BY-SA 4.0)viaCommons Wikimedia
2.’Eubacteria (263 10) Bacterial capsule’By Doc. RNDr. Josef Reischig,(CC BY-SA 3.0)viaCommons Wikimedia