Difference Between Capsid and Envelope

关键区别 - 衣壳与信封

Virus（也被称为病毒) is an infective particle composed ofnucleic acidmolecule covered with a protein capsid. Viruses show living as well as non-living characteristics. Two major component of a virus particle are viral genome and the protein coat. The viral genome is packaged inside the protein capsid. In some viruses, the protein capsid is surrounded by another cover called envelope. The envelope is composed of a lipid bilayer that contains viral proteins which help the virus to bind to the host cells. Protein capsid and envelope play key roles in viral infection, including virus attachment to host cell, entry into cell, release of the proteins of the capsid, assembly, and packaging of the newly synthesized viral particle, transfer of the viral genetic material from one cell to another, etc. The key difference between capsid and envelope is thatcapsid is a coat made up of proteinswhile信封是由脂质组成的膜。All virion particles possess a capsid while only enveloped viruses possess an envelope.

内容

1.Overview and Key Difference
2.什么是衣帽
3.什么是信封
4.Similarities Between Capsid and Envelope
5。Side by Side Comparison – Capsid vs Envelope in Tabular Form
6。概括

What is Capsid?

Viruses are the simplest and tiniest of microorganisms found on the Earth. Viruses consist of genetic material (DNA or RNA) enclosed in a protective protein coat called a capsid. Therefore, viral capsid can be defined as the protein shell that surrounds thegenome病毒粒子的。衣壳主要由蛋白质组成。它由几个称为蛋白质的低聚结构亚基组成protomers。Several protomers (5 to 6) collectively make the individual protein subunits of the protein capsid. These individual protein subunits are known as胶囊。Capsomeres are arranged in a precise and highly repetitive pattern around the nucleic acid. These capsomeres are the smallest morphological units of capsids that are only visible under the electron microscope. A single virion has a large number of capsomeres.

蛋白质衣壳可以以不同的形状排列。三种基本形状被识别为螺旋形，二十面体或多面体和复杂的排列。大多数病毒具有螺旋形或二十面膜的衣壳结构。一些病毒，尤其是感染病毒的细菌（噬菌体），具有复杂的衣壳结构。在螺旋病毒中，胶囊在基因组周围以螺旋形式排列。在二十面体病毒中，胶囊在20个等边三角形面中排列。

Protein capsid performs several functions. It protects the genetic material of the virion particle. It aids in transferring virus particles between host organisms. The spikes located on the viral capsid aid bothspecificity和病毒感染。尖峰是糖蛋白与宿主细胞上某些受体结合的突起。

什么是信封?

一些病毒被额外的脂质双层膜包围。该脂质膜被称为viral envelope。它包含phospholipids蛋白质并包围病毒式衣壳。它主要来自宿主细胞膜。病毒在病毒复制和释放过程中获取该包膜。包膜中的病毒蛋白有助于病毒与宿主细胞受体结合。病毒包络在病毒感染中起主要作用，包括宿主识别和进入。它有助于病毒的附着，将遗传物质转移到宿主细胞以及细胞之间等。病毒包膜还参与确定病毒稳定性特征，例如对化学和物理失活的抗性。

根据包膜的存在和不存在，病毒被分为两组称为包膜病毒和非发育病毒（裸病毒）。裸病毒不包含周围的信封nucleocapsid。Compared to enveloped viruses, naked viruses are more stable and can survive a long time in the environment.

What are the Similarities Between Capsid and Envelope?

• 衣壳和信封是参与viral infection。
• Both contain proteins.
• 两者都是保护盖。

CAPSID和信封有什么区别？

Capsid vs Envelope
Capsid is the protein shell surrounding the genetic material of the virus.	Envelope is the outer structure that encloses the nucleocapsids of some viruses.
作品
衣壳由蛋白质组成。	Envelope is composed of phospholipids and proteins.
Cover
Capsid covers the viral genome.	包络覆盖核衣壳（病毒基因组 +衣壳）。
在场
所有病毒都存在capsid。	Envelope is present only in some viruses.

概括– Envelope vs Capsid

Envelope and capsid are two structural parts in viruses. Capsid is the protein shell which surrounds the viral genome. Envelope is the lipid membrane acquired by the viruses from the host cells. It covers the nucleocapsid. Envelope is composed of both phospholipids and proteins. This is the difference between capsid and envelope. Capsids and envelopes together determine the method of viral entry into and exit from host cells. Both structures also determine the stability and the resistance of the virus.

Download PDF Version of Envelope vs Capsid

You can download PDF version of this article and use it for offline purposes as per citation notes. Please download PDF version hereDifference Between Capsid and Envelope.

参考：

1.“病毒信封。”维基百科。Wikimedia基金会，2017年3月26日。Available here.2017年7月11日。
2. “Capsid.” Wikipedia. Wikimedia Foundation, 08 July 2017. Web.Available here。2017年7月11日。

Image Courtesy:

1. Thomas Splettstoesser（www.scistyle.com）的“与RNA的Helical Capsid” - 自己的作品(CC BY-SA 4.0)viaCommons Wikimedia
2. “Enveloped icosahedral virus” By Nossedotti (Anderson Brito) – Own work(CC BY-SA 3.0)viaCommons Wikimedia