Extracellular Polymeric Substances (EPS)

-

Extracellular Polymeric Substances (EPS) are complex, high-molecular-weight polymers secreted by microorganisms, including bacteria, algae, fungi, and archaea. They create a hydrated matrix that surrounds cells, enabling them to adhere to surfaces and form biofilms. This matrix not only provides protection but also facilitates communication and resource sharing among microbial communities.


Composition of Extracellular Polymeric Substances 

 Extracellular Polymeric Substances is a heterogeneous mix of organic molecules, including:

  • Polysaccharides: Long-chain carbohydrates that provide structure and hydration.

  • Proteins: Enzymes and structural components that enhance functionality.

  • Lipids: Contribute to adhesion and barrier properties.

  • Nucleic Acids: Extracellular DNA (eDNA) plays a structural role and enables genetic exchange.

Physical Properties:

  • Hydrated gel-like consistency (up to 97% water).

  • Sticky and adhesive, promoting surface attachment.

  • High resilience to environmental stressors.

        Water makes up the majority of the EPS matrix, ensuring its gel-like consistency and adaptability.

Functions of Extracellular Polymeric Substances

        Biofilm Formation:

    • Acts as a scaffold for microbial communities, enabling cells to adhere to each other and surfaces.
    • Provides a stable microenvironment for cell-to-cell interactions.   

        Protection: 

    • Shields microorganisms from UV radiation, desiccation, toxins, and antimicrobial agents.
    • Mitigates environmental stresses like pH fluctuations and salinity change

        Nutrient Retention: 

    • Captures and stores nutrients, supporting microbial survival in nutrient-scarce environments.

        Cell Communication:

    • Facilitates quorum sensing, enabling coordinated microbial behavior and biofilm maturation.

        Surface Interaction: 

    • Enhances adhesion to natural and artificial surfaces, contributing to biofilm stability

Extracellular Polymeric Substance in Algae

Algae, both microalgae and macroalgae, produce EPS with unique roles:

  • Enhances buoyancy for optimal photosynthesis.

  • Aids in adhesion to surfaces in aquatic environments.

  • Plays a role in carbon sequestration by trapping organic carbon and forming marine snow

Ecological Importance of EPS

  • Soil Stability: Promotes soil aggregation and improves fertility.

  • Aquatic Systems: Influences sediment stability and supports microbial mats.

  • Biogeochemical Cycles: Facilitates nutrient cycling, impacting carbon, nitrogen, and phosphorus turnover.

Industrial and Biotechnological Applications

  1. Environmental Applications:

    • Used in wastewater treatment for pollutant degradation.

    • Plays a role in bioremediation, immobilizing heavy metals and degrading hydrocarbons.

  2. Food Industry: EPS like xanthan gum and alginate are used as thickeners and stabilizers. 

  3. Agriculture: EPS-producing microbes enhance soil health, promote plant growth, and improve water retention in arid soils.

  4. Medical Relevance:

    • Understanding EPS is vital for managing biofilm-associated infections, as biofilms often resist antibiotics and immune responses.
    • Anti-biofilm strategies target EPS to disrupt microbial communities.

Comments

Post a Comment

Popular posts from this blog

Factors Affecting Alcohol Fermentation

-
Understanding the Key Factors that Influence the Fermentation Process Alcohol Fermentation •        Alcohol fermentation is a biological process where sugars (like glucose) are converted into alcohol (ethanol) and carbon dioxide by yeast. •        It's used in producing alcoholic beverages and in some biofuel production processes. Overview of the Alcohol Fermentation Process •        Yeast consumes sugars (glucose, fructose). •        Yeast metabolizes sugar into ethanol and CO₂. •        Byproducts : Ethanol, carbon dioxide, and heat.   Temperature •        Optimal Temperature Range : 20-30°C (68-86°F) •        Effects of Low Temperature : Slower fermentation, yeast activity decreases. •        Effects of High Temperature : Y...
Read more

Management of Bacterial Diseases in Mushrooms

-
Image
1. Bacterial Blotch (Pseudomonas tolaasii) Symptoms: Yellow-brown, water-soaked lesions or blotches on mushroom caps, especially on Agaricus bisporus (button mushrooms). Lesions often become darker, giving the mushroom a discolored, slimy appearance. Affected mushrooms may have reduced market value due to blemishes. Management: Sanitation: Disinfect surfaces, tools, and growing areas regularly. Proper Ventilation: Maintain good air circulation and reduce humidity to below 85% to inhibit bacterial growth. Use of Bactericides: Some growers apply bactericides like chlorine dioxide or hydrogen peroxide at safe concentrations to control bacterial blotch. Avoid Overwatering: Keep water application to a minimum, and avoid splashing water on the mushrooms. pH Adjustment: Maintain the casing layer pH above 7.0 to make it less conducive for P. tolaasii. 2. Mummy Disease (Pseudomonas agarici)   ...
Read more

Cyanophage

-
Image
Cyanophages are a group of viruses that specifically infect cyanobacteria (formerly called blue-green algae) These phages play a significant role in aquatic ecosystems by regulating cyanobacterial populations, influencing biogeochemical cycles, and contributing to gene transfer across microbial communities The term "cyanophage" is derived from "cyano" (cyanobacteria) and "phage" (to eat), indicating their parasitic relationship with cyanobacteria. Their presence is critical in controlling harmful algal blooms and maintaining microbial diversity in marine and freshwater habitats. History   Discovery 1955 : First cyanophage discovered by Safferman & Morris in freshwater. Named the LPP-1 group (hosts: Lyngbya , Plectonema , Phormidium ).   Morphology Era (1970s–1980s) Use of electron microscopy to classify phages. Identified tailed viruses (Myoviridae-like). Host range expanded to include filamentous and colonial cyanobacteria Marine Cyanophage Discov...
Read more