Related Experiment Video
Updated: Apr 19, 2026
12:57
Isolation and Chemical Characterization of Lipid A from Gram-negative Bacteria
Published on: September 16, 2013
33.2K
Bacterial lipoteichoic acid enhances cryosurvival.
Charles V Rice1, Amy Middaugh, Jason R Wickham
1Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK, 73019, USA, rice@ou.edu.
Extremophiles : Life Under Extreme Conditions
|December 6, 2014
Summary
Lipoteichoic acid (LTA), a bacterial cell wall component, enhances freeze tolerance in microbes. This discovery suggests LTA could play a key role in cryoprotection for bacteria.
Area of Science:
- Microbiology
- Biochemistry
- Cryobiology
Background:
- Antifreeze proteins confer freeze tolerance in some organisms but are generally absent in microbes.
- Microbes exhibit remarkable survival at sub-freezing temperatures, indicating unknown cryoprotective mechanisms.
Purpose of the Study:
- To investigate the potential of lipoteichoic acid (LTA) as a cryoprotective agent in bacteria.
- To explore the role of LTA in bacterial freeze tolerance.
Main Methods:
- Addition of lipoteichoic acid (LTA) to Bacillus subtilis cultures.
- Measurement of cell viability using the resazurin assay after freezing.
- Low-temperature microscopy to observe ice crystal formation.
Main Results:
- 1% w/v LTA significantly increased B. subtilis survival rate to 50% after freezing.
- Glycerol at 1% w/v yielded similar cryoprotective results.
- B. subtilis showed some innate freeze tolerance even without cryoprotectants.
Conclusions:
- Lipoteichoic acid (LTA) acts as a cryoprotective agent in Gram-positive bacteria.
- LTA may protect intracellular water by influencing ice crystal formation within biofilms and planktonic cells.
- The findings suggest a novel mechanism for microbial survival at low temperatures.
More Related Videos
Related Concept Videos
01:19Formation of Lipopolysaccharides
1.1K
Lipopolysaccharides (LPS) are crucial components of the outer membrane of Gram-negative bacteria, serving both structural and functional roles. It contributes to membrane stability and protects bacteria from host immune responses. LPS is composed of three major regions—lipid A, a core oligosaccharide, and an O antigen. The biosynthesis and assembly of LPS involve a highly coordinated set of enzymatic reactions and transport mechanisms. Additionally, LPS is recognized as an endotoxin,...
1.1K
01:29Biosynthesis of Lipids
931
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...
931
01:20Endospores and Sporulation
7.8K
Endospores are specialized, dormant cells primarily formed by Gram-positive bacteria, including Bacillus and Clostridium, enabling survival under extreme environmental conditions. Due to their unique composition and formation process, these structures are highly resistant to physical and chemical insults, such as extreme heat, ultraviolet and ionizing radiation, desiccation, and toxic chemicals. Rare instances of endospore-like structures have also been observed in some Gram-negative bacteria,...
7.8K
01:31Defense Against Bacterial Pathogens
3.7K
The human immune system is a complex network of cells, tissues, and organs that work together to defend the body against bacterial infections. It consists of various immune cells, each playing a specific role in the defense mechanism.
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
3.7K
01:22Bacterial Cell Wall
5.6K
The bacterial cell wall is an essential structural component that encases the plasma membrane, preserving cellular integrity, determining shape, and protecting against osmotic stress. This rigid yet flexible structure primarily comprises peptidoglycan, a polymer that forms a mesh-like matrix conferring mechanical strength and flexibility.Peptidoglycan Composition and StructurePeptidoglycan, the core of the bacterial cell wall, comprises alternating units of N-acetylglucosamine (NAG) and...
5.6K
01:12Bacterial Toxins
109
Bacterial toxins are sophisticated virulence factors that enable pathogenic bacteria to interact with, invade, and damage host tissues. These toxins fall broadly into two types: protein exotoxins, which are secreted into the environment and target specific host receptors, and lipopolysaccharide endotoxins, which are structural components of the bacterial outer membrane released primarily during bacterial lysis or membrane shedding. Exotoxins generally act more selectively, binding to cell...
109