関連する実験動画
Updated: May 5, 2026

06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
23.6K
バクテリオファージT4の細胞穿孔装置の構造
Shuji Kanamaru1, Petr G Leiman, Victor A Kostyuchenko
1Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907-1392, USA.
Nature
|February 2, 2002
まとめ
バクテリオファージT4は,そのベースプレート (遺伝子製品5と遺伝子製品27の複合体) を使用して,Escherichia coliに感染します. この構造は,細胞膜を貫穿し,DNAの侵入のためにペプチドグリカン層を消化させる針のように作用します.
科学分野:
- 構造生物学 構造生物学とは
- 微生物学 微生物学とは
- ウイルス学 ウイルス学 ウイルス学
背景:
- バクテリオファージT4は,Escherichia coliに感染するための洗練されたメカニズムを使用しています.
- ファグの尾のベースプレートは,細胞の侵入に不可欠であり,尾の繊維とDNAの放出を調節します.
- 遺伝子産物 (gp) 5-gp27複合体は,細胞外膜に浸透し,ペプチドグリカン層を分解するために不可欠です.
研究 の 目的:
- gp5-gp27複合体の高解像度結晶構造を決定するために.
- 細胞感染におけるバクテリオファージT4ベースプレートの機能の構造的基礎を解明する.
- ベースプレート・テール・チューブ・アセンブリの文脈の中でgp5-gp27複合体を視覚化するために.
主な方法:
- (gp5-gp27) 3複合体の2.9 Å解像度構造を決定するためのX線結晶学.
- クリオ電子顕微鏡で,水晶構造をベースプレート-テイルチューブ組の17 Åの解像度マップに合わせる.
主要な成果:
- 結晶構造は,gp5のカルボキシ末端ドメインを三連鎖ベータヘリックスとして顕示し,膜を刺す針を形成する.
- gp5の中央リゾーシムドメインは,ペプチドグリカン層を消化するために配置されています.
- gp5のアミノ端末ドメインはgp27のシリンダーに挿入され,潜在的にDNA放出チャネルを形成します.
結論:
- gp5-gp27複合体は,膜浸透,ペプチドーグリカン分解,そして潜在的にDNA転位を司る明確なドメインを有している.
- この構造的な洞察は,分子レベルでバクテリオファージT4の感染機構の詳細な理解を提供します.
- この発見は,ファグと宿主の相互作用と治療上の応用に関するさらなる研究のための基盤を提供します.
関連する概念動画
Lytic Cycle of Bacteriophages
60.5K
Bacteriophages, also known as phages, are specialized viruses that infect bacteria. A key characteristic of phages is their distinctive “head-tail” morphology. A phage begins the infection process (i.e., lytic cycle) by attaching to the outside of a bacterial cell. Attachment is accomplished via proteins in the phage tail that bind to specific receptor proteins on the outer surface of the bacterium. The tail injects the phage’s DNA genome into the bacterial cytoplasm. In the...
60.5K
Lysogenic Cycle of Bacteriophages
50.0K
In contrast to the lytic cycle, phages infecting bacteria via the lysogenic cycle do not immediately kill their host cell. Instead, they combine their genome with the host genome, allowing the bacteria to replicate the phage DNA along with the bacterial genome. The incorporated copy of the phage genome is called the prophage. Some prophages can re-activate and enter the lytic cycle. This often occurs in response to a perturbation, such as DNA damage, but can also transpire in the absence of...
50.0K
Intracellular Movement of Viruses and Bacteria
3.0K
Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
3.0K
Mechanism of Conjugation
1.6K
Bacterial conjugation is a mechanism of horizontal gene transfer that enables the exchange of genetic material between bacterial cells through direct contact. This process is facilitated by a donor cell carrying a conjugative plasmid, which encodes genes necessary for pilus formation, DNA replication, and transfer. The conjugative plasmid plays a central role in initiating and executing the transfer of genetic material.The tra region of the conjugative plasmid encodes proteins responsible for...
1.6K
Viral Replication: Lytic Cycle
3.0K
Bacteriophages, or phages, are viruses that specifically infect bacteria. Among them, T-even bacteriophages, such as T4, exhibit a well-characterized lytic replication cycle in Escherichia coli (E. coli). This process ensures the rapid proliferation of the virus while ultimately leading to the destruction of the bacterial host.Attachment and DNA InjectionThe infection process begins with the recognition and binding of the T4 phage to the E. coli cell surface. Tail fibers of the phage...
3.0K
DNA Bacteriophages
1.6K
Bacteriophages, or phages, are viruses that specifically infect bacteria, utilizing their genetic material to hijack host cellular machinery for replication. DNA bacteriophages employ single-stranded DNA (ssDNA) or double-stranded DNA (dsDNA) genomes. These phages exhibit diverse replication strategies and host interactions, influencing their ecological roles and applications in biotechnology and medicine.ssDNA BacteriophagesssDNA phages, with their small genomes, utilize unique strategies to...
1.6K

