Related Experiment Video
Updated: May 24, 2025
09:40
Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
12.1K
Bacteria- and Phage-Derived Proteins in Phage Infection
Olga I Guliy1, Stella S Evstigneeva1
1Institute of Biochemistry and Physiology of Plants and Microorganisms, Saratov Scientific Centre of the Russian Academy of Sciences (IBPPM RAS), 410049 Saratov, Russia.
Frontiers in Bioscience (Landmark Edition)
|February 28, 2025
Summary
Bacteriophage enzymes degrade bacterial membranes and peptidoglycans during infection. Understanding these phage-bacterium interactions is key to developing phage-derived therapeutics.
Area of Science:
- Microbiology
- Virology
- Biochemistry
Background:
- Bacteriophages (phages) exert significant evolutionary pressure on prokaryotes.
- Bacterial antiphage defense systems are diverse, but their mechanisms are often unclear.
- Understanding phage-bacterium interactions is crucial for practical phage applications.
Purpose of the Study:
- To review key phage enzymes involved in the initial stages of bacterial infection.
- To analyze the mechanisms of phage enzymes that degrade bacterial membranes and peptidoglycans.
- To explore the therapeutic potential of bacteriophage-derived proteins.
Main Methods:
- Literature review of phage enzymes and their functions.
- Analysis of phage proteins involved in host cell interaction and lysis.
- Examination of enzymes responsible for bacterial membrane and peptidoglycan degradation.
Main Results:
- Identified key phage enzymes including polysaccharide depolymerases (e.g., endosialidases, alginate lyases) and peptidoglycan hydrolases (e.g., endolysins).
- Described phage proteins like holins, endolysins, and spanins crucial for progeny release during the lytic cycle.
- Highlighted how phage proteins modulate host target proteins to facilitate infection.
Conclusions:
- Phage enzymes play critical roles in overcoming bacterial defenses and enabling infection.
- Detailed understanding of these enzymes is essential for advancing phage-based technologies.
- Bacteriophage-derived proteins show therapeutic promise, particularly endolysins.
Related Concept Videos
01:30Lytic Cycle of Bacteriophages
70.1K
Bacteriophages, also known as phages, are specialized viruses that infect bacteria. A key characteristic of phages is their distinctive “head-tail” morphology. A phage begins the infection process (i.e., lytic cycle) by attaching to the outside of a bacterial cell. Attachment is accomplished via proteins in the phage tail that bind to specific receptor proteins on the outer surface of the bacterium. The tail injects the phage’s DNA genome into the bacterial cytoplasm. In the...
70.1K
00:43Lysogenic Cycle of Bacteriophages
61.7K
In contrast to the lytic cycle, phages infecting bacteria via the lysogenic cycle do not immediately kill their host cell. Instead, they combine their genome with the host genome, allowing the bacteria to replicate the phage DNA along with the bacterial genome. The incorporated copy of the phage genome is called the prophage. Some prophages can re-activate and enter the lytic cycle. This often occurs in response to a perturbation, such as DNA damage, but can also transpire in the absence of...
61.7K
02:53CRISPR and crRNAs
16.5K
Bacteria and archaea are susceptible to viral infections just like eukaryotes; therefore, they have developed a unique adaptive immune system to protect themselves. Clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins (CRISPR-Cas) are present in more than 45% of known bacteria and 90% of known archaea.
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
The CRISPR-Cas system stores a copy of foreign DNA in the host genome and uses it to identify the foreign DNA upon reinfection. CRISPR-Cas has three different...
16.5K
01:23Antimicrobial Proteins
864
Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
Interferons
Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
864
01:10Intracellular Movement of Viruses and Bacteria
2.8K
Intracellular bacteria and viruses often comprise a group of highly infectious pathogens that can cause several diseases. Bacterial pathogens include those belonging to the genus Rickettsia responsible for conditions such as rocky mountain spotted fever and the Mediterranean spotted fever; Chlamydia, a genus responsible for a sexually transmitted disease; Coxiella burnetii, an agent responsible for Q fever. Viral pathogens include vaccinia—a poxvirus, and herpes simplex virus—a...
2.8K
01:31Defense Against Bacterial Pathogens
1.4K
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...
1.4K