外膜ウシロームは,腸内バクテロイドのグリカン吸収を媒介する
Joshua B R White1, Augustinas Silale2, Matthew Feasey2
1Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
Nature
|June 7, 2023
まとめ
バクテロイドは 食中の砂糖を分解する 複雑なタンパク質の機械を 使います これらの構造は 細菌がヒトの微生物群の 栄養素を捕捉し 輸送する方法を示しています
科学分野:
- 微生物学
- 構造生物学
- 人間の微生物群の研究
背景:
- バクテロイドは食事中のグリカンを代謝する重要な腸内細菌です.
- グライカンの吸収は,外膜のSusCDタンパク質複合体によって媒介されます.
- 外膜の成分の相互作用は栄養素の獲得に不可欠ですが,理解は不十分です.
研究 の 目的:
- Bacteroides thetaiotaomicronにおけるグリカン利用に関与する外膜タンパク質複合体の組成と機能を調査する.
- これらの細菌システムによるグリカン捕獲と輸送のメカニズムを解明する.
主な方法:
- 単粒子の冷凍電子顕微鏡 (cryo-EM) を使用して構造を決定した.
- 構造は,グリカン基板の不在と存在の両方で得られた.
- そのメカニズムを理解するために,形状の変化を分析した.
主要な成果:
- 特定された,安定した,多成分グリカンを使用する機械は"utilisomes"と呼ばれています.
- ユーティリゾームは,追加の外膜タンパク質を組み込むコア SusCD トランスポーターに組み込まれます.
- Cryo-EM構造は,グリカン捕獲に不可欠な基板誘発型変化を明らかにした.
結論:
- バクテロイドは,効率的なグリカン獲得のために多タンパク質の"ユートリソーム"を使用します.
- これらの構造は,基板の捕獲と輸送のための調整されたメカニズムを示しています.
- 腸内微生物群の機能についての洞察が得られる.
さらに関連する動画
12:29Generation of Null Mutants to Elucidate the Role of Bacterial Glycosyltransferases in Bacterial Motility
Published on: March 11, 2022
2.7K
08:51Profiling of Permethylated Mucin O-glycans Using Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry
Published on: June 20, 2025
593
関連する概念動画
Oligosaccharide Assembly
3.5K
Protein glycosylation starts in the ER lumen and continues in the Golgi apparatus. Glycosyltransferases catalyze the addition of sugar molecules or glycosylation of proteins. Usually, these enzymes add sugars to the hydroxyl groups of selected serine or threonine residues to form O-linked glycans or the amino groups of asparagine residues to form N-linked glycans. Different positions on the same polypeptide chain can contain differently linked glycans.
Multiple sugar molecules that may or may...
Multiple sugar molecules that may or may...
3.5K
Membrane Carbohydrates
7.1K
The plasma membrane is a dynamic barrier composed of lipids, proteins, and carbohydrates. It is the epicenter of many cellular processes required for cell growth and survival. Carbohydrates have unique structural and chemical properties that help the plasma membrane to carry out its functions effectively.
Membrane carbohydrates do not have any hydrophobic region and are exclusively located on the cell's outer surface. The addition of sugar molecules or glycosylation of proteins happens in...
Membrane carbohydrates do not have any hydrophobic region and are exclusively located on the cell's outer surface. The addition of sugar molecules or glycosylation of proteins happens in...
7.1K
Bacterial Phylum Tenericutes
450
The phylum Tenericutes, which includes the single class Mollicutes, comprises bacteria that lack cell walls. The term "Mollicutes" derives from the Latin word mollis, meaning "soft." These organisms are among the smallest known and are commonly referred to as mycoplasmas due to the prominence of the genus Mycoplasma, which includes well-known human pathogens. Despite their inability to stain gram-positively (a result of their lack of cell walls), mycoplasmas are phylogenetically related to the...
450
Surface Membrane Barriers
2.6K
The skin and mucous membranes serve as the primary line of defense against pathogens by providing both physical and chemical protection. These barriers are essential in preventing the entry and establishment of microbes, thereby maintaining the integrity of the host.
The outer layer of the skin, the epidermis, is a robust barrier comprising layers of closely packed keratinized cells. This dense arrangement prevents microbes from penetrating the body. The periodic shedding of epidermal cells...
The outer layer of the skin, the epidermis, is a robust barrier comprising layers of closely packed keratinized cells. This dense arrangement prevents microbes from penetrating the body. The periodic shedding of epidermal cells...
2.6K
Biosynthesis of Lipids
537
Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis...
537
Carrier-Mediated Transport
1.2K
Carrier-mediated transport is a pivotal process in drug absorption, particularly for lipid-insoluble drugs, and encompasses facilitated diffusion and active transport. Facilitated diffusion allows drugs to move along their concentration gradient without energy expenditure, while active transport utilizes ATP to drive drug movement against this gradient.
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
1.2K
