Name: lipopolysaccharides and gram-negative defense
Uploaded: 2025-06-12T09:39:09.000Z
Duration: 1 min 19 s
Channel: JoVE

지방다당류 또는 LPS는 그람 음성 박테리아에 필수적이며, 구조적 지지를 제공하고 면역 회피를 돕습니다. LPS는 핵심 올리고당인 지질 A와 O 항원으로 구성됩니다. 지질 A 생합성은 우리딘 디포스페이트 N-아세틸글루코사민과 함께 세포질에서 시작되며, 이는 효소 아실화를 거칩니다. 그것은 추가적인 지방산이 추가됨에 따라 순차적인 변형을 겪는 테트라-아실화된 중간체를 형성합니다. 추가 아실화는 헥사-아실화된 지질 A를 생성합니다. 다음으로, 글리코실전이효소는 코어 올리고당을 지질 A에 순차적으로 부착합니다.이 지질 A-코어 복합체는 MsbA 수송체에 의해 내막을 가로질러 운반됩니다. 한편, O 항원은 세포질의 운반체 지질에 조립되어 주위(periplasm)로 뒤집힙니다. 주실장에서 O 항원 단위는 중합되고 지질 A-코어에 결찰되어 완전한 LPS를 형성합니다. 마지막으로, 지질다당류 수송 시스템은 LPS를 주위층을 가로질러 이동시키고 이를 외막에 통합하여 박테리아 방어를 강화합니다.

지질다당류(lps)의 형성

Formation of Lipopolysaccharides

&#51648;&#51656;&#45796;&#45817;&#47448;(LPS)&#45716; &#44536;&#46988; &#51020;&#49457;&#44512;&#51032; &#50808;&#47561;&#50640;&#49436; &#51473;&#50836;&#54620; &#44396;&#49457; &#50836;&#49548;&#47196;, &#44396;&#51312;&#51201; &#48143; &#44592;&#45733;&#51201; &#50669;&#54624;&#51012; &#49688;&#54665;&#54633;&#45768;&#45796;. &#51060;&#45716; &#47561;&#51032; &#50504;&#51221;&#49457;&#50640; &#44592;&#50668;&#54616;&#44256; &#49464;&#44512;&#51012; &#49689;&#51452; &#47732;&#50669; &#48152;&#51025;&#51004;&#47196;&#48512;&#53552; &#48372;&#54840;&#54633;&#45768;&#45796;. LPS&#45716; &#49464; &#44032;&#51648; &#51452;&#50836; &#50689;&#50669;&#8212;&#51648;&#51656; A, &#54645;&#49900; &#50732;&#47532;&#44256;&#45817;, O &#54637;&#50896;&#8212;&#51004;&#47196; &#44396;&#49457;&#46121;&#45768;&#45796;. LPS&#51032; &#49373;&#54633;&#49457; &#48143; &#51312;&#54633;&#51008; &#44256;&#46020;&#47196; &#51312;&#51221;&#46108; &#54952;&#49548; &#48152;&#51025;&#44284; &#49688;&#49569; &#47700;&#52964;&#45768;&#51608;&#51012; &#54252;&#54632;&#54633;&#45768;&#45796;. &#46608;&#54620; LPS&#45716; &#50644;&#46020;&#53665;&#49888;&#51004;&#47196; &#51064;&#49885;&#46104;&#47728;, Toll-like receptor 4(TLR4)&#47484; &#53685;&#54644; &#49689;&#51452;&#50640;&#49436; &#44053;&#54620; &#47732;&#50669; &#48152;&#51025;&#51012; &#50976;&#48156;&#54633;&#45768;&#45796;. &#51060; &#48152;&#51025;&#51008; &#50684;&#51613;&#51012; &#51068;&#51004;&#53420; &#49688; &#51080;&#51004;&#47728;, &#49900;&#54620; &#44221;&#50864; &#54056;&#54792;&#49457; &#49660;&#53356;&#47196; &#51060;&#50612;&#51656; &#49688; &#51080;&#49845;&#45768;&#45796;.
&#51648;&#51656; A &#49373;&#54633;&#49457;
LPS&#51032; &#46021;&#49457; &#49457;&#48516;&#51064; &#51648;&#51656; A&#45716; &#49464;&#54252;&#51656;&#50640;&#49436; &#54633;&#49457;&#46104;&#47728;, &#50976;&#47532;&#46356;&#45348;&#51060;&#53944; &#51060;&#51064;&#49328; N-&#50500;&#49464;&#54008;&#44544;&#47336;&#53076;&#49324;&#48124; (UDP-GlcNAc) &#51004;&#47196; &#49884;&#51089;&#46121;&#45768;&#45796;. &#54952;&#49548; &#50500;&#49892;&#54868; &#48152;&#51025;&#51060; &#49692;&#52264;&#51201;&#51004;&#47196; &#51060;&#47336;&#50612;&#51256; UDP-GlcNAc&#50640; &#51648;&#48169;&#49328;&#51060; &#52628;&#44032;&#46104;&#50612; &#53580;&#53944;&#46972;-&#50500;&#49892;&#54868;&#46108; &#51648;&#51656; A &#51204;&#44396;&#52404;&#44032; &#54805;&#49457;&#46121;&#45768;&#45796;. &#51060; &#51473;&#44036;&#52404;&#45716; &#52628;&#44032;&#51201;&#51064; &#50500;&#49892;&#54868; &#44284;&#51221;&#51012; &#44144;&#52432; &#49457;&#49689;&#54620; &#54757;&#49324;-&#50500;&#49892;&#54868;&#46108; &#51648;&#51656; A&#47196; &#48320;&#54872;&#46121;&#45768;&#45796;. &#51068;&#48512; &#49464;&#44512;(&#50696;: &#49332;&#47784;&#45356;&#46972;&#50752; &#50696;&#47476;&#49884;&#45768;&#50500;)&#45716; &#51648;&#51656; A&#47484; &#45908; &#49688;&#51221;&#54616;&#50668; &#51064;&#49328;&#50640;&#53444;&#50732;&#50500;&#48124; &#46608;&#45716; &#50500;&#48120;&#45432;&#50500;&#46972;&#48708;&#45432;&#50724;&#49828;&#47484; &#52628;&#44032;, &#54637;&#48120;&#49373;&#47932; &#54185;&#53440;&#51060;&#46300;&#50640; &#45824;&#54620; &#51200;&#54637;&#49457;&#51012; &#44053;&#54868;&#54633;&#45768;&#45796;. &#50756;&#51204;&#55176; &#51312;&#47549;&#46108; &#51648;&#51656; A&#45716; &#45236;&#47561;&#50640; &#44256;&#51221;&#46104;&#50612; &#51080;&#51004;&#47728;, &#52628;&#44032;&#51201;&#51064; &#49688;&#51221;&#51060; &#51060;&#47336;&#50612;&#51656; &#46412;&#44620;&#51648; &#45824;&#44592;&#54633;&#45768;&#45796;.
&#54645;&#49900; &#50732;&#47532;&#44256;&#45817;&#44284; O &#54637;&#50896;&#51032; &#51312;&#54633;
&#54645;&#49900; &#50732;&#47532;&#44256;&#45817;&#51008; &#49692;&#52264;&#51201;&#51004;&#47196; &#51648;&#51656; A&#50640; &#44208;&#54633;&#46121;&#45768;&#45796;. &#51060; &#54645;&#49900; &#50689;&#50669;&#51008; &#47561;&#51032; &#47924;&#44208;&#49457;&#50640; &#54596;&#49688;&#51201;&#51060;&#47728;, O &#54637;&#50896;&#51032; &#44264;&#44201; &#50669;&#54624;&#51012; &#54633;&#45768;&#45796;. O &#54637;&#50896;&#51008; &#48152;&#48373;&#46104;&#45716; &#45817; &#45800;&#50948;&#47196; &#44396;&#49457;&#46108; &#45796;&#45817;&#47448;&#47196;, &#51648;&#51656; &#50868;&#48152;&#52404;&#51064; &#50868;&#45936;&#52852;&#54532;&#47112;&#45776; &#51064;&#49328;&#50640;&#49436; &#48324;&#46020;&#47196; &#54633;&#49457;&#46121;&#45768;&#45796;. O &#54637;&#50896;&#51032; &#44600;&#51060;&#50752; &#45817; &#51312;&#49457;&#51008; &#49464;&#44512; &#51333;&#50640; &#46384;&#46972; &#45804;&#46972;&#51648;&#47728;, &#51060;&#45716; &#47732;&#50669; &#51064;&#49885; &#48143; &#48337;&#50896;&#49457;&#50640; &#50689;&#54693;&#51012; &#48120;&#52841;&#45768;&#45796;.
LPS &#51312;&#54633; &#48143; &#49688;&#49569;
&#51648;&#51656; A&#44032; &#54645;&#49900; &#50732;&#47532;&#44256;&#45817;&#50640; &#44208;&#54633;&#46104;&#47732;, MsbA &#54540;&#47532;&#54168;&#51060;&#49828; &#54952;&#49548;&#44032; &#46160; &#44396;&#51312;&#47484; &#45236;&#47561;&#51012; &#44032;&#47196;&#51656;&#47084; &#49688;&#49569;&#54633;&#45768;&#45796;. &#46041;&#49884;&#50640;, &#44256;&#48516;&#51088;&#54868;&#46108; O &#54637;&#50896;&#51008; &#54168;&#47532;&#54540;&#46972;&#51608;&#51004;&#47196; &#54540;&#47549;&#46121;&#45768;&#45796;. &#47532;&#44172;&#51060;&#49828; &#54952;&#49548;&#45716; O &#54637;&#50896;&#51012; &#51648;&#51656; A-&#54645;&#49900; &#50732;&#47532;&#44256;&#45817; &#48373;&#54633;&#52404;&#50640; &#44208;&#54633;&#54616;&#50668; LPS &#44396;&#51312;&#47484; &#50756;&#49457;&#54633;&#45768;&#45796;.
&#49457;&#49689;&#54620; LPS&#45716; Lpt(&#51648;&#51656;&#45796;&#45817;&#47448; &#49688;&#49569;) &#49884;&#49828;&#53596;&#51012; &#53685;&#54644; &#50808;&#47561;&#51004;&#47196; &#49688;&#49569;&#46121;&#45768;&#45796;. &#51060;&#45716; LPS&#51032; &#51201;&#51208;&#54620; &#50948;&#52824; &#51648;&#51221;&#51060; &#51060;&#47336;&#50612;&#51648;&#46020;&#47197; &#48372;&#51109;&#54616;&#45716; &#45796;&#45800;&#48177;&#51656; &#48373;&#54633;&#52404;&#51077;&#45768;&#45796;. &#51060; &#49688;&#49569; &#44284;&#51221;&#51008; ATP&#50640; &#51032;&#51316;&#51201;&#51060;&#47728;, &#45236;&#47561;&#50640; &#51080;&#45716; LptBFG &#48373;&#54633;&#52404;&#44032; &#54596;&#50836;&#54620; &#50640;&#45320;&#51648;&#47484; &#51228;&#44277;&#54633;&#45768;&#45796;. &#51201;&#51208;&#54620; LPS &#50948;&#52824; &#51648;&#51221;&#51008; &#50808;&#47561;&#51012; &#44053;&#54868;&#49884;&#53020; &#49464;&#44512;&#51032; &#54637;&#49373;&#51228;, &#49689;&#51452; &#47732;&#50669; &#51064;&#51088; &#48143; &#54872;&#44221; &#49828;&#53944;&#47112;&#49828;&#50640; &#45824;&#54620; &#51200;&#54637;&#49457;&#51012; &#51613;&#44032;&#49884;&#53429;&#45768;&#45796;.

지질다당류(LPS)의 형성

&#51648;&#51656;&#45796;&#45817;&#47448;(LPS)&#45716; &#44536;&#46988; &#51020;&#49457;&#44512;&#51032; &#50808;&#47561;&#50640;&#49436; ...

Education

교육

JoVE Core

Microbiology

미생물학

Unit

단위

Microbial Metabolism

미생물 대사

KEY TERMS AND CONCEPTS

주요 용어 및 개념

지방다당류의 형성

lipopolysaccharides and gram-negative defense

Lipopolysaccharides (LPS) are important parts of the outer membrane of Gram-negative bacteria. They help stabilize the membrane and help protect bacteria from host immune responses. LPS has three main parts: lipid A, a core oligosaccharide, and an O antigen.

LPS biosynthesis and assembly depend on a coordinated set of enzymes and transport steps. The molecule is also known as an endotoxin. It can activate Toll-like receptor 4 (TLR4) in the host and trigger strong immune responses. In severe cases, this response can lead to inflammation and septic shock.

Lipid A is the toxic part of LPS. It is made in the cytoplasm, beginning with uridine diphosphate N-acetylglucosamine, or UDP-GlcNAc. Enzymes add fatty acids in a stepwise acylation process to form a tetra-acylated precursor. Further acylations produce mature hexa-acylated lipid A. Some bacteria, including Salmonella and Yersinia, add phosphoethanolamine or aminoarabinose to lipid A. These changes can increase resistance to antimicrobial peptides. The finished lipid A stays anchored in the inner membrane.

The core oligosaccharide is added next by glycosyltransferases. This core region helps maintain membrane integrity and acts as a scaffold for the O antigen. The O antigen is a repeating sugar chain made separately on the lipid carrier undecaprenyl phosphate. Its length and sugar makeup vary among bacterial species. These differences can affect immune recognition and virulence.

After lipid A is linked to the core oligosaccharide, the MsbA flippase moves both parts across the inner membrane. At the same time, the polymerized O antigen is flipped into the periplasm. A ligase then joins the O antigen to the lipid A-core complex to finish LPS assembly. The mature LPS is carried to the outer membrane by the Lpt transport system, which is a multiprotein complex. The inner-membrane LptBFG complex uses ATP for energy. Proper LPS placement strengthens the outer membrane and increases resistance to antibiotics, host immune factors, and environmental stressors.

Lipopolysaccharides and Gram-Negative Defense

lipopolysaccharides-and-gram-negative-defense

microbial nutrition

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introduction to metabolism

Metabolism: Energy Use and Biomolecule Synthesis

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glycolysis

Glycolysis and Pyruvate Fate

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other glycolytic pathways

Pentose Phosphate Pathway and Entner-Doudoroff

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cellular respiration

Cellular Respiration: ATP Production Pathways

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electron transport chain components

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chemiosmosis and atp synthesis

Electron Transport Chain Powers ATP Output

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respiration pathways

TCA Cycle and Energy Pathways

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microbial fermentation

Fermentation Products in Microbes

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metabolism of chemolithotrophs

How Chemolithotrophs Make ATP

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Microbes Use Proteins for Energy

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lipid catabolism

How Microbes Break Down Fats for Energy

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oxygenic photosynthesis

How Plants Make Oxygen and ATP

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Bacterial Light Capture Without Oxygen

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Microbial Carbon Fixation Pathways

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biosynthesis of polysaccharides

Activated Sugars for Polysaccharide Synthesis

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inorganic nitrogen assimilation

Nitrogen Uptake by Microbes

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sulfur assimilation

Sulfur Uptake and Cysteine Synthesis

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amino acid biosynthetic pathways

Amino Acid Building from Cell Metabolites

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biosynthesis of nucleic acids

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biosynthesis of lipids

How Membrane Lipids Vary Across Life

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formation of lipopolysaccharides

Lipopolysaccharides (LPS) are important parts of the outer membrane of Gram-negative bacteria. They help stabilize the membrane and help protect bacteria from host immune responses. LPS has three main parts: lipid A, a core oligosaccharide, and an O antigen. LPS biosynthesis and assembly depend on a coordinated set of enzymes and transport steps. The molecule is also known as an endotoxin. It can activate Toll-like receptor 4 (TLR4) in the host and trigger strong immune responses. In severe...

key terms and concepts

Learn how lipopolysaccharides are built, moved, and attached in Gram-negative bacteria, and how LPS helps protect cells and trigger immune responses.

Lipopolysaccharides and Gram-Negative Defense | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

Lipopolysaccharides and Gram-Negative Defense

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