人間や動物の腸内微生物群に多く存在する巨大ファグ群
Research square
|September 2, 2025
まとめ
ヒトの腸内の大型ウイルスであるジャンボ・ゲート (Jug) ファージが特定され,特徴づけられました. これらのファージは広範囲に広がり 腸内微生物群の生態系に影響を及ぼす可能性があります
科学分野:
- 微生物学
- ウイルス学
- ゲノミクス
背景:
- 巨大ファージは世界中に分布しているが,ヒトの腸内微生物群におけるその役割は十分に理解されていない.
- ヒトの腸内生態系における 巨大ウイルスの多様性と生態学的影響については さらに調査が必要です
研究 の 目的:
- ヒトの腸内における巨大なファージの流行,ゲノム特性,生態学的役割を特徴づける.
- これらの大きなファグの進化史と伝播パターンを調査する.
主な方法:
- ヒトの腸内サンプルをメタゲノム解析して 巨大なファグゲノムを 特定し組み立てます
- 比較ゲノミクスは,ゲノム全体の配列アイデンティティを分析し,水平的に取得された遺伝子を識別します.
- 宿主間の進化的関係と分布を決定する 系統遺伝分析
主要な成果:
- 人間の腸内メタゲノミックの約1.1%を占める大型ゲノム (360~402kbp) を有するジャンボ腸内ファグの発見と特徴付け.
- ジャグファージは,バクテロイドおよび/またはフォケイコラ種に感染すると予測されています.
- 主要なグループ内の高全体のゲノム類似性 (> 90%) にもかかわらず,大きなターミナーゼサブユニットは低い同一性 (38 - 57%) を示し,水平遺伝子転送を示した.
- ヒトと動物の腸内メタゲノムから1,500以上のジャグファグゲノムが回収され,広範囲に分布し,共通遺伝子の含有量があり,頻繁なクロスホスト伝播が示唆されています.
- ジャグファージは,新しいカルシウム転位型P型ATPアゼ遺伝子を含め,高い転写活性を示します.
結論:
- ジャグファージはヒトの腸内ウイルスの重要な構成要素であり,知られている巨大なファージの多様性を拡大しています.
- 広範な分布と遺伝子交換メカニズムは 腸内微生物コミュニティの形成に 重要な役割を果たすことを示唆しています
- ジャグファージは,ヒトの腸内微生物群の生態と機能における潜在的な鍵となる存在として特定されています.
関連する概念動画
Bacterial Phylum Verrucomicrobiota
103
The phylum Verrucomicrobiota comprises at least four characterized orders, with most species classified within the order Verrucomicrobiotales. Members of this phylum are either aerobic or facultatively aerobic, with the ability to ferment sugars. A notable exception is the genus Methylacidiphilum, which consists of aerobic methanotrophs. Additionally, some Verrucomicrobiota establish symbiotic relationships with protists. These bacteria are widely distributed across various environments,...
103
Bacterial Phylum Proteobacteria
131
Proteobacteria, one of the largest and most diverse bacterial phyla, encompasses a wide range of Gram-negative bacteria distinguished by their outer membrane composed of lipopolysaccharides. These microorganisms exhibit various metabolic capabilities, including phototrophy, chemolithotrophy, and heterotrophy, and thrive in diverse environments from soil to aquatic systems and host-associated niches. The phylum is divided into six classes: Alphaproteobacteria, Betaproteobacteria,...
131
Bacterial Phylum Bacteroidota
121
The phylum Bacteroidota includes over 700 species classified into four primary orders: Bacteroidales, Cytophagales, Flavobacteriales, and Sphingobacteriales. These gram-negative, non-sporulating rods exhibit saccharolytic capabilities and can be aerobic or fermentative, encompassing obligate aerobes, facultative aerobes, and obligate anaerobes. Many species display gliding motility, though some are nonmotile or use flagella. The genus Bacteroides is well-studied due to its significant role in...
121
Bacterial Phylum Tenericutes
88
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...
88
Bacterial Flora of the Large Intestine
641
The gut microbiome is formed by a vast and diverse community of bacteria that colonizes our large intestine. These bacteria start residing in the gut from birth and continue diversifying throughout life, influenced by factors such as diet, lifestyle, and stress. The gut bacterial community also includes bacteria from food and those that enter the colon through the anus.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.
641
Bacterial Phylum Firmicutes
144
Firmicutes is a diverse phylum of Gram-positive bacteria characterized by a low GC content in their genomes. This phylum includes organisms with monoderm or diderm cell envelopes, highlighting a complex evolutionary history. Firmicutes comprises several major orders, including Lactobacillales, Clostridiales, and Bacillales, which exhibit remarkable diversity in their morphology, metabolism, and ecological roles.The order Lactobacillales includes lactic acid bacteria, which are fermentative...
144


