Related Experiment Video
Updated: Jul 15, 2025
10:59
Enrichment of Bacterial Lipoproteins and Preparation of N-terminal Lipopeptides for Structural Determination by Mass Spectrometry
Published on: May 21, 2018
8.7K
Comparative Structure Analysis of the Multi-Domain, Cell Envelope Proteases of Lactic Acid Bacteria
Lise Friis Christensen1, Magnus Haraldson Høie2, Claus Heiner Bang-Berthelsen1
1National Food Institute, Technical University of Denmark, Kemitorvet, DK-2800 Kongens Lyngby, Denmark.
Microorganisms
|September 28, 2023
Summary
Lactic acid bacteria cell envelope proteases (CEPs) exhibit diverse structures and functions. This study used AlphaFold 2 to predict CEP structures, revealing novel domain architectures relevant for food development and health.
Area of Science:
- Microbiology
- Structural Biology
- Biochemistry
Background:
- Lactic acid bacteria (LAB) possess extracellular proteolytic systems featuring cell envelope proteases (CEPs) with subtilisin-like domains.
- CEPs display varied proteolytic activities despite sequence similarity, with structural data previously limited to dairy and human strains.
Purpose of the Study:
- To investigate the structural diversity and prevalence of CEPs across different LAB origins, including plant-derived strains.
- To utilize computational methods for predicting CEP structures, overcoming experimental challenges associated with their size and cell-envelope attachment.
Main Methods:
- Employed AlphaFold 2, a structure prediction software, to analyze 21 CEP homologs.
- Conducted comparative analysis of predicted 3D structures to delineate domain boundaries and identify novel domain architectures.
Main Results:
- Revealed novel domain architectures of CEP homologs, not confined to specific LAB species or ecological niches.
- Identified distinct cell envelope attachment domains and a cell wall-spanning domain, alongside fibronectin type-III-like domains C-terminal to the protease domain.
- Demonstrated that domain variations influence CEP stability, proteolytic activity, and adhesive properties.
Conclusions:
- The structural diversity of CEPs is broader than previously understood, with implications for their function.
- Understanding CEP domain architecture offers potential for manipulating proteolytic activity for applications in food development and human health.
Keywords:
AlphaFold 2 modelscell envelope proteaseextracellular proteolysislactic acid bacteriaprotein structuresubtilaseMore Related Videos
11:18Isolation and Preparation of Bacterial Cell Walls for Compositional Analysis by Ultra Performance Liquid Chromatography
Published on: January 15, 2014
16.3K
09:09Semi-Quantitative Analysis of Peptidoglycan by Liquid Chromatography Mass Spectrometry and Bioinformatics
Published on: October 13, 2020
4.4K
Related Concept Videos
01:29Archaeal Cell Wall
37
Archaeal cell walls are structurally and compositionally distinct from their bacterial counterparts, lacking the characteristic peptidoglycan layer found in most bacteria. Instead, archaeal cell walls exhibit remarkable diversity, utilizing materials such as pseudomurein, polysaccharides, and proteins to construct their protective outer layers. This structural flexibility is closely tied to archaea's ecological adaptability.S-Layers: The Common Archaeal Cell WallThe S-layer is the most...
37
01:22Lysosomal Hydrolases
3.8K
Lysosomes are the site for the degradation of macromolecules and biological polymers released during membrane trafficking events such as secretory, endocytic, autophagic, and phagocytic pathways. The membrane-enclosed area of the lysosome, called the lumen, contains hydrolytic enzymes active in an acidic environment. These acid hydrolases are functional at a pH between 4.5 and 5 and are involved in cellular processes such as cell signaling, energy metabolism, restoration of the plasma membrane,...
3.8K
01:18Outer Layers of the Cell Envelope
39
The outermost layers of prokaryotic cells play a critical role in their survival, virulence, and interaction with the environment. These layers, often composed of polysaccharides, polypeptides, or proteins, form protective and adhesive structures that vary in organization and function.Capsules and Slime LayersCapsules are highly organized, tightly bound layers of polysaccharides that firmly attach to the bacterial cell wall. These structures serve as formidable protective barriers, preventing...
39
01:31Lysosomes
19.0K
Lysosomes are membrane-enclosed spherical sacs derived from the Golgi apparatus. The most important function of the lysosome is degrading macromolecules and biological polymers that are released during membrane trafficking events such as the secretory, endocytic, autophagic, and phagocytic pathways. The degradation is carried out by several hydrolytic enzymes active in an acidic environment of the lysosomal lumen. These acid hydrolases are involved in cellular processes such as cell signaling,...
19.0K
01:19Formation of Lipopolysaccharides
34
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,...
34
01:29Cytoskeletal Proteins in Bacteria
3.4K
Bacterial cells were initially considered simple, randomly organized structures lacking a cytoskeleton. However, the discovery of cytoskeleton homologs in bacteria led to the change of this opinion. Bacterial cytoskeletal filaments regulate the cell shape, cell polarity, cell division, and partitioning of plasmids during cell division. It was later discovered that bacterial cytoskeletal proteins, mainly actin and tubulin homologs, are diverse compared to their eukaryotic counterparts. On the...
3.4K