The Phage

Exploring Phage T4: The Most Popular Virus of Microbes

Fri, 30 Dec 2022 06:59:09 +0200

Phages or Bacteriophages are viruses that mainly infect bacteria. They are highly specialized and have evolved over time to become the most abundant biological entities on Earth. Phage T4 is one of the most well-studied phages and is among the most popular phages used in research. In this article, we will be exploring phage T4, its structure, its life cycle, and its applications in research and medicine.

Bacteriophages: The microscopic enemy of the dairy industry

Fri, 23 Dec 2022 09:59:06 +0200

The majority of people relate viruses with diseases that affect plants and animals only, what we don't know is that being the smallest living entity in the universe, viruses are capable of infecting other microorganisms like bacteria. Having viruses affecting bacteria has proven to be beneficial to the human race, especially in recent years where there was a rise in antibiotics resistance and they are used as antibiotics alternatives. These viruses are known as bacteriophages and sometimes termed as phages in short form, these entities are of variety and infect every kind of bacteria that has so far been discovered by scientists while maintaining their specificity (meaning every bacteria has got a certain variety of phages that can specifically infect its strain). Bacteria being well known for their diseases doesn't mean all of them cause one, and in fact, we have a lot of bacteria that are beneficial to our lives either direct or indirect. Just to mention a few some bacteria help in nitrogen fixation in plants, decomposition, act as normal flora on our skins and stomachs and some are even used in food processing.

Lactic acid bacteria (LAB) are among the most beneficial microorganisms in the food industry. These microorganisms produce lactic acid from sugar fermentation. For this reason, they have been used for thousands of years in the production of fermented milk products, like yogurt and cheese, among others. Just like other bacteria, they are also prone to attacks, phages penetrate their genetic materials and command the bacteria to act as a piece of machinery for making viral copies before the cell burst and die off to release new particles.

Dairy products. photo by Change food

Effect of Lactic Acid Bacteria on milk during processing

The LABs trigger a microbial process where they transform the –sugar in milk- into lactic acid. That acid modifies the structure of the milk proteins making them curdle and reproducing the same effect on the product’s texture. Besides, it provides the milk with that characteristic slightly bitter taste. It was proved that these microorganisms provide beneficial effects on the health of those who consume them. Furthermore, it supplements the health of the bacterium present in the intestinal flora promoting the good performance of the digestive system. For this reason, they are very important for the dairy industry considering the context of growing interest in the market of probiotic products.

Effect of phage on the action of Lactic Acid Bacteria (LAB) during milk processing

Phage activity causes decreased starter (Starter is a set of LAB bacteria that are readily available to initiate the fermentation process) activity in cheese and fermented milk manufacturing, resulting in fermentation in which acid production is markedly reduced or, in extreme cases, totally blocked. This failure in fermentation develops low-quality products that are not safe from a microbiological point of view because they can contain contaminants and/or pathogens that do not have to compete with the lactic bacteria that protect the product (probiotic way).

Where is the source of phage contamination in the dairy industry?

Raw milk is considered to be the principal source of phages, either as free virions or as prophages present in wild strains of lactic acid bacteria (LAB), and constitutes the primary phage entranceway to the industrial environment. Sometimes equipment, people, and the environment can be the source of contamination although this kind of contamination is much easier to handle just by modifying sanitation procedures and decontaminating surfaces.

Methods used to inactivate Dairy Bacteriophages contaminants

Phages are difficult to eliminate because they rapidly disseminate in dairy plants. The following are commonly used methods in eliminating phage contaminants in dairy processing plants.

Heat Treatments

Most dairy processing plants use heat to kill a number of microbes from milk, among others phages are heavily affected especially when subjected to the high heat of 70°C for a long time. The conditions recommended by the International Dairy Federation (IDF; 90°C for 15 min) to guarantee complete phage inactivation. For cheese production, low-temperature long time (LTLT, 63°C for 30 min) or high-temperature short time (HTST, 72°C for 15 s) pasteurization were traditionally applied. Ultra-high-temperature (UHT) processing, also called ultra-pasteurization (more than 135°C for 1–2 s), is a sterilization treatment as it produces spores destruction. However, this high heating can cause Maillard browning and negatively affect the taste and smell of dairy products. The milk used for yogurt production is generally treated at 80°C for 30 min or at 95°C for 10 min. Regardless of the high efficiency of this heat treatment to inactivate microorganisms, it is not always effective against dairy bacteriophages.

2. Chemical treatment (Biocides)

A biocide should fulfill several criteria to be usable in the food industry, for example possessing a fast antimicrobial activity, ease of application, low cost, lack of negative impact on the final product, and degradation into harmless final products. However, the inactivation of bacteriophages was taken into consideration only recently as a criterion of biocides selection, which is reflected by an increasing number of studies directed to quantify their effectiveness in this sense. Ethyl alcohol (ethanol), isopropyl alcohol (isopropanol), sodium hypochlorite, and peracetic acid are among the most common biocides.

3. High-Pressure Treatments

High-pressure processing is one of the most promising because it combines maximal retention of the chemical and physicochemical product properties with efficient germ reduction. The most studied and applied pressure-based processes are high hydrostatic pressure (HHP) and high-pressure homogenization (HPH). HPH is a high hydrodynamic process during which the fluid is forced to pass through a small orifice and then subjected to an ultra-rapid decompression. The sudden fall in the local pressure of the fluid at constant temperature leads to the nucleation and growth of vapor bubbles (or cavities) within the body of liquid, the collapse of which could transmit several localized forces to surfaces or particles, including the microbial cell.

4. Photocatalysis

Photocatalysis is a process in which light energy is used to drive pairs of chemical reactions. This method is well utilized if phage particles are aerosolized in the air. The capability of bacteriophages to remain in the air for long periods makes bioaerosols one of the most important dispersion routes of virions.

In the mid-1930s, the first adverse impact of bacteriophages on dairy fermentation was reported. Despite sanitary precautionary measures, starter strain rotations, and the persistent development of new phage-resistant bacterial strains, phages continue to be one of the most common and economically significant causes of fermentation failure. Bacteriophages cause problems in industrial dairy fermentations all over the world due to their natural presence in the milk environment. They are difficult to eradicate due to their short latent period, relatively large burst size, and/or resistance to pasteurisation. Phage-induced bacterial cell lysis causes failed or slow fermentation, a decrease in acid production, and a reduction in milk product quality (nutritive value, taste, texture, and so on), resulting in significant economic losses.

References

Role of Bacteriophages in the Implementation of a Sustainable Dairy Chain by Gutierez et al, (2019)
Review: efficiency of physical and chemical treatments on the inactivation of dairy bacteriophages by Guglielmotti et al, (2012).
Marcó, M. B., Suárez, V. B., Quiberoni, A., & Pujato, S. A. (2019). Inactivation of Dairy Bacteriophages by Thermal and Chemical Treatments. Viruses, 11(5), 480. https://doi.org/10.3390/v11050480
Lactic Acid Bacteria Resistance to Bacteriophage and Prevention Techniques to Lower Phage Contamination in Dairy Fermentation by Szczepankowska et al, (2013).

Phage mediated biocontrol of phytopathogens

Thu, 22 Dec 2022 20:59:13 +0200

ⒸBIOTEC

Phytopathogens have always been a barrier to the agricultural industry's ability to meet rising food demands. Annual crop loss due to plant disease is estimated at $220 billion USD or 14.1% of total crop loss. Crop loss can be caused by biotic organisms such as fungi, viruses, bacteria, and nematodes, as well as abiotic factors such as environmental factors. Phytopathogens infect interspecific plants and pose a significant threat to the global food trade. Antibiotics and copper sprays have been used in existing management programs, which have not only disturbed the microflora, causing their accumulation in the environment but have also facilitated bacterial transformation into multi-drug resistance (MDR) strains. Safer alternatives, such as bacteriophages, have been thought of in order to protect the environment and its contents while lowering the risk of superbug development.

Unlocking Food Safety with Bacteriophages: A Natural Solution for Food Safety

Fri, 16 Dec 2022 01:04:04 +0200

Food safety is an important issue in our society. With the rise of bacteria-related illnesses, it is essential to know how to protect ourselves and our families from these dangerous microorganisms. One way to do this is to use bacteriophages, which are tiny viruses that can kill bacteria. In this blog post, we will explore what bacteriophages are, the benefits they offer, how they can be used to improve food safety, and more.

Creator: fcafotodigital | Credit: Getty Images

Phage typing for bacterial strain detection and identification

Tue, 13 Dec 2022 10:36:36 +0200

What is phage typing?

Phage typing is a quick, accurate, and low-cost phenotypic method that uses bacteriophage specificity to detect and identify single strains of bacteria. Is simple to understand this concept once you know the phage life cycle. Bacteriophages use one of two mechanisms: lytic or lysogenic. In the first, the phage inserts its genetic material into the cell, converting it into a factory for the production of more phages, which will eventually lyse the host. During lysogenic action, the phage's injected genome is incorporated into the cell's DNA, transforming it into a prophage that will generate progeny when reproduction conditions are favorable. During bacterial cell division, the phage nucleic acids multiply along with the bacteria's genome.

ⒸSzaleniec et al (2019)

The Lytic and Lysogenic Cycles of Bacteriophages

Mon, 12 Dec 2022 00:33:22 +0200

A virus is a microscopic intracellular parasitic organism. It infects the host cell and uses its chemical machinery to make its own proteins and nucleic acids. While these particles are well-known pathogens for multicellular organisms, nothing prevents them from terrorizing the microscopic unicellular organisms, such as archae and bacteria. Viruses known as bacteriophages or simply phages infect bacteria. Like any other virus, phages cannot reproduce on their own; they require the assistance of a supporting cell (host cell). Because the host bacteria that supports their replication must be living and metabolically active, dormant cells such as persister in a biofilm may not be infected by bacteriophages until they regain their activity. Phage has one of the better-understood virus life cycles because its relatively easier to culture in the laboratory. They exhibit two kinds of life cycles which are lytic and lysogenic.

Phage lytic and lysogenic cycles

Bacteriophage therapy: The potential treatment option for diabetic wounds

Fri, 09 Dec 2022 19:08:09 +0200

Wounds are injuries as a result of a break in the continuity of any bodily tissue. They include cuts, scrapes, scratches, and punctured skin just to mention a few. They are frequently the result of an accident. Wounds usually heal within a couple of weeks in most cases. However, some medical conditions, such as diabetes, can slow down the healing process and make infections more likely. The good news is that there are ways for people with diabetes to promote wound healing. Vitamin C, zinc, and protein are all nutrients that have been scientifically proven to help your body heal wounds more quickly. Workouts also help to improve insulin sensitivity by increasing the efficiency with which blood sugar enters your cells, thereby promoting healing and health.

Temperate and lysogenic infection: Are they the same?

Mon, 28 Nov 2022 14:19:28 +0200

Lysogenic cycle

Lysogenic infection

An infection that results in prophage genome replication but does not explicitly involve virion production except after subsequent prophage induction. Lytic infections, on the other hand, involve both phage replication and virion production. Phage-genome replication and virion production do not occur in the context of pseudo-lysogenic infections. Lysogenic infections should not be confused with "temperate-phage infections," because temperate phages can infect both strategies (lytic and lysogenic). Since most phages can infect bacterial cells and cause lysis despite having a lysogenic cycle, temperate phages are more common.

bacteriophage vs prophage: What is a difference?

Tue, 22 Nov 2022 10:41:07 +0200

The primary distinction between prophage and bacteriophage is that prophage is a viral genome that has been integrated into a bacterial genome, whereas bacteriophage is the actual virus that infects the bacteria. Prophages are also bacteriophages that go through the lysogenic cycle by integrating their genome into the bacterial genome. Bacteriophages can transform into prophages after integrating their nucleic acids into the bacterial genome. Once integrated, the segment of the genome is known as a prophage. This integration into the host genome is accomplished by an enzyme called integrase, which is encoded by lysogenic bacteriophages. Prophages can undergo excision from the host genome in order to enter into the lytic cycle; research indicates that this process is triggered by external factors.

Are bacterial biofilms susceptible to bacteriophage attack?

Sat, 05 Nov 2022 14:07:05 +0200

The study of the pathogenesis of diseases caused by harmful bacteria aids in the development of knowledge on how to battle these microbes. Bacteria are prokaryotic microorganisms that cause disease in humans and animals. Some of these bacteria are part of the organism's microflora and play important roles in the well-being of their host organisms; a good example of this symbiosis is non-pathogenic Escherichia coli, which aids in sugar digestion in mammals' guts. In some cases, when these microbes grow uncontrollably or penetrate the barrier, they cause diseases. Staphylococcus aureus, Staphylococcus epidermidis, and Escherichia coli, among much other normal flora, have been linked to diseases in their host.

Isolation of Pseudomonas bacteriophages from fish gastro intestinal tract

Mon, 03 Oct 2022 17:29:48 +0200

Fish plays a vital role in the human diet, and consumption per capita is increasing; however, the expansion of industry and agriculture causes contamination of the natural and man-made aquatic environment, which affects the health of organisms, raising safety concerns about its use for human consumption. Consumption of fish products, particularly raw or undercooked fish, is frequently linked to human diseases. As a result, it is critical to research these pathogens in order to ensure the safety of fish. The presence of various bacterial species in fish, including those pathogenic to humans, has been linked to direct contact with contaminated water or feed. Pseudomonas species are bacterial pathogens that infect fish.

Culture plate showing phage plaques on
Pseudomonas bacterial lawn Photo
by Hilary kinabo
(Student Makerere university)

Pseudomonas species are Gram-negative, aerobic bacilli measuring 0.5 to 0.8, μm by 1.5 to 3.0 μm. Motility is by a single polar flagellum. Species are distinguished by biochemical and DNA hybridization tests and they belong to the family Pseudomonadaceae and which includes four genera: Frateuria, Pseudomonas, Xanthomonas, and Zoogloea. Bacteria colonization can be observed on fish skin and gills.

Misuse of antibiotics as prophylactic agents in disease prevention is common and contributes to the development of antibiotic resistance Alternatives to antibiotics such as antibacterial vaccines, bacteriophage, and their lysins, have been applied to curtail the increasing emergence of antibiotic-resistant bacteria due to the imprudent application of antibiotics in aquaculture

Bacteriophages (phages), viruses infecting bacterial species, demonstrate clear antimicrobial activity against an array of resistant species, with high levels of specificity and potency. These are viral species that specifically infect bacteria by injecting their genetic material into the host bacterial cell. They are ubiquitous in aquatic and terrestrial ecosystems and in the microbiome of animal species. In fish, phages are present on skin surfaces and intestines, where they act as a natural predator to the bacterial microbiome.

Bacteriophages: Nature's Solution to Drug-Resistant Bacteria

Mon, 03 Oct 2022 16:33:44 +0200

Bacteria are microorganisms that are present everywhere on Earth. They are essential for the proper functioning of many ecosystems and are used in a variety of industries, such as food production and wastewater treatment. However, some types of bacteria can cause disease in humans, animals, and plants. Infectious diseases caused by bacteria are a major global health problem. In recent years, the problem of drug-resistant bacteria has become increasingly prevalent. This is because the use of antibiotics to treat bacterial infections has led to the evolution of antibiotic-resistant strains of bacteria. In recent years phages have been sought as being the potential alternative to antibiotics in treating superbugs.

photo credit :ZMESCIENCE.com

What is bacteriophage transduction?

Thu, 15 Sep 2022 07:11:27 +0200

What is phage transduction?

Is the process by which a bacteriophage (phage) shuttles or transfers bacterial genes from one bacterial cell (donor cell) to another (recipient cell). Among the genes that bacteria can acquire from phages via transduction are virulence and antibiotic resistance genes.

Mechanisms of genetic transduction. Generalized (top), specialized (middle), and lateral transduction (bottom). The viral genome (in red) first undergoes theta replication, followed by rolling circle replication. Chiang et al (2019)

Isolation of edwardsiella-specific bacteriophages from fish

Sun, 11 Sep 2022 16:26:47 +0200

Aquaculture, the culture of all types of aquatic animals and plants in fresh, back rush, and marine water environments, is one of the fastest-growing food-producing sectors. This industry frequently suffers heavy losses due to diseases caused by pathogens such as multi-drug resistant bacteria, which are easily transmitted through water and thus capable of infecting a variety of animal and plant species. Edwardsiella species, gram-negative facultative aerobic rod-shaped Enterobacteriaceae, are among the infectious aquaculture pathogens that attack fish. Edwardsiella tarda and Edwardsiella ictulari have been linked to the development of Edwardsiella septicemia (also known as ES, edwardsiellosis, emphysematous putrefactive disease of catfish, fish gangrene, and red disease) in channel catfish, eels, and flounder, as well as Enteric septicemia of catfish.

Edwardsiella tarda has also been linked to zoo infections in a variety of animals. It is a zoonotic disease that can infect a wide range of animals beyond fish, including amphibians, reptiles, and mammals. This bacteria is found in pond water, mud, and the intestines of fish and other marine animals, as well as freshwater species. On the other hand, Edwardsiella ictaluri, the causative agent of enteric septicemia in catfish (ESC), is one of the most common fish pathogens affecting farm-raised channel catfish.

Antibiotics have traditionally been used to control bacterial disease in aquaculture farms and hatcheries. However, the indiscriminate use of antibiotics in aquaculture has resulted in the emergence and spread of antibiotic-resistant bacteria, rendering the culture system ineffective. Another major source of concern is the presence of antibiotic residues in aquatic products, which has resulted in decreased consumption. Aquaculture farmers have also been slow to adopt control and preventive measures due to the high cost and marginal effectiveness of mediated feeds.

Jumbo phage chimallin (ChmA) protein: The answer to CRISPR-Cas bacterial defense system?

Fri, 19 Aug 2022 12:48:57 +0200

Loughlin et, 2020

Jumbo phages are bacteriophages (phages) with genetic information (genomes) larger than 200 kilobases. These phages are known as "jumbo" because they have a huge genome size. In addition, they exhibit several novel characteristics not seen in smaller genome phages, which distinguish jumbo phages in aspects of genome and virion structure, progeny propagation, and evolution. According to some studies, jumbo phages can be useful in various ways in this era of antibiotic resistance. They have proven to be more effective than other phages, particularly when dealing with bacterial defense systems and infectivity.

Phagemids: Phage plasmid hybrid vector

Fri, 12 Aug 2022 12:18:09 +0200

Due to its development as a hybrid of filamentous phage and plasmids, a phagemid is a cloning vector that can grow as a plasmid and be packaged as single-stranded DNA in viral proteins. Phagemid vectors differ from commonly used plasmids in that they can be loaded into the capsid of phages because they contain a phage packaging region of DNA from the genome of the phage. When compared to other vectors, phagemids have several advantages, such as producing single-stranded DNA that is ideal for sequencing and being easily used in site-directed mutagenesis.

Structure of Phagemids

A phagemid can be replicated as a normal plasmid expression vector and packaged in viral particles as single-stranded DNA. Phagemids have a double-stranded plasmid replication origin (ori) as well as an f1 ori for single-stranded replication and packaging into virus particles. Many popularly used plasmids have an f1 ori and thus are phagemids. They also contain the intergenic region of filamentous phages, which allows phagemid replication via helper phages and phagemid single-strand DNA packing. The selective marker region allows the selection of transformants, and the promoter site is responsible for directing the start of multiple cloning sites (where signal peptide, restriction sites, and tag are) while the coat protein site code for the virion capsid packaging.

Adapted from Qi et al

Top 4 most used Phage Display Systems (The Phage blog)

Tue, 05 Jul 2022 13:35:26 +0200

The most often utilized bacteriophages in phage display are filamentous bacteriophages from E. coli (f1, fd, and M13), while T4, T7, and phage have also been used. On this page (Application of phage display), you may read more about the many uses of this technology.

Electron microscopy of filamentous bacteriophage. Credit: Petrenko, 2018

Inoviridae (Filamentous phages): Bacteriophages with a unique replication cycle

Sun, 03 Jul 2022 14:08:32 +0200

Bacteriophage is a term used to describe viruses that infect bacteria and archaea. While most phages are 'micro predators' that kill their bacterial hosts, filamentous phages collaborate with their hosts. These viruses are even simpler than the T-phage studied by the phage group, owing to their ease of manipulating their genetic contents. Filamentous phages have a low burden on bacteria and compensate by providing services that aid in the formation of better biofilms, delivering toxins and other factors that increase virulence, or modifying their behavior to provide novel motile activity to their bacterial hosts.

Game Theory between Bacteriophages and Pathogens

Thu, 19 May 2022 08:41:00 +0200

Game theory is widely used to analyze economic and social behaviors. Actually, the game theory is also used to analyze biological behavior as well, just as the study from TelAviv University published in the journal Nature Microbiology indicated. Researchers discovered that, just like humans, bacteriophages (or phages) can weigh the benefits of all options before making an informed decision - whether it's time to come out of dormancy and kill their bacterial host.

Can a bacteriophage infect a human cell?

Wed, 18 May 2022 18:04:26 +0200

Can a bacteriophage infect a human cell?

It's an intriguing question that has scientists scratching their heads over the possibility of these "minute guys" (phages) wreaking havoc on our bodies. This same question would be asked by someone who wants to know if phages are safe for humans, especially when used as a treatment alternative. Concerns about their safety when used live (without attenuation) never left the minds of those in charge of approving drugs for human/animal use. For so long, this has been a nightmare for phage-based pharmaceutical companies, but rules are finally allowing many phage products to enter the market.

Bacteriophages, which are viruses that infect bacteria, have resurfaced as powerful regulators of bacterial populations in natural ecosystems. Phages infiltrate the human body in the same way that they do other natural environments, to the point where they are the most numerous in the human virome. Despite the fact that phages in the human body have been reported for decades, this was only revealed in recent metagenomic studies. The impact of phage presence in humans has yet to be determined. Still, as in marine environments, a clear role in regulating bacterial populations is possible, which could have an impact on human health.

Furthermore, phages are excellent vehicles for genetic transfer, and they aid in the evolution of bacterial cells in the human body by horizontally spreading and acquiring DNA. The abundance of phages in the human body does not go unnoticed, and the immune system reacts to them, though to what extent is unknown. Finally, unnoticed phage presence in human samples can influence and bias microbiological and molecular results. Given the evidence, some studies suggest that their interference requires more attention.

What type of bacteria do bacteriophages infect?

Despite bacteriophages' specificity in infecting a specific species of host bacteria, there are no known bacteria that do not have phages to infect them. Bacteria evolve to resist attacks, whereas bacteriophages, as living entities, evolve new attack strategies.

Is there a possibility of a bacteriophage infecting human cells?

Human cells are not infected by bacteriophages. As a result, they cannot infect humans. They only infect bacteria that are specific to them. Your immune system efficiently removes the bacteriophages from your system once they have destroyed all of the bacteria they have infected. Bacteriophages are self-limiting and harmless to humans;. However, they may indirectly cause undesired activities like transferring antibiotic resistance genes (ARGs) from one bacteria to another, driven mainly by lysogenic phages.

What is the role of bacteriophages and the human microbiome?

The bacteriophage ("phage") is a virus that eats bacteria; however, a better term would be natural bacteria predator. Phages can be found in all types of microbial environments. The conflict between phages and bacteria dates back to the dawn of life. Bacteriophages are very picky about the bacteria they attack. Because of this selectivity, phages can eliminate a specific type of harmful bacteria while leaving all other bacteria alone, with no known side effects on the human body.

The majority of the viral population in the human gut microbiome is made up of phages. Caudovirales are the most common order of bacteriophages found in the gut microbiota. The order is made up of three families of lytic viruses that attack specific types of bacteria and archaea: Myoviridae (long contractile tails), and Siphoviridae (long non-contractile tails), and Podoviridae (short non-contractile tails) (short non-contractile tails).

The viral component of the gut microbiota has received a lot of attention in the last decade. Bacteriophages used in supplements in the United States; LH01-Myoviridae, LL5-Siphorviridae, T4D-Myoviridae, and LL12-Myoviridae were selected primarily to target pathogenic Escherichia coli strains. Because of the selective nature of phage preference for bacteria targeting, a non-invasive approach to therapy is possible. Scientists can isolate bacteriophages that are effective against pathogenic bacteria, and the treatment is completely safe for both the human body and the existing beneficial bacteria.

Immune system, gut microbiome, and phages

The study of the effects of bacteriophages on the human immune system is also expanding. While some studies show that phages can have a negative impact on the immune system, others show that bacteriophages can strengthen the system. It is important to note that bacteriophages are not all classified in the same way. The distinction between virulent and temperate phages is critical to understand. It directly reflects whether bacteriophages contribute to the immune system's health or cause harm.

By nature, temperate phages or bacteriophages that use lysogeny use the bacterium as a host organism and have their unique symbiotic relationship. They will do whatever it takes to keep their host safe and protected from invasion and, ultimately, death. Some studies show that this defensive mechanism can also assist bacterial biofilm formation. It is only when the prophage (embedded phage in the bacterium's DNA) finds that all hope is lost for the host's survival that it can switch to the lytic cycle, bursting out of the bacterium to survive.

Lytic bacteriophages or virulent phages utilize the lysis of the bacterium and are used in phage therapy. Their mechanism is more straightforward; they target the bacterium, insert their genetic material, and rapidly multiply within the bacterium, ultimately killing the host by bursting out of the organism and releasing the newly formed phages. Positive immunomodulating effects were seen in studies that used lytic phages to treat bacterial infections, such as Escherichia virus T4, a phage from the subfamily of Tevenvirinae from the family of Myovirinae.

Probiotics, prebiotic & bacteriophages

Many people today recognize probiotics as supplements that deliver beneficial bacteria to our microbiome. These bacteria become a part of the gut ecosystem, joining the symbiotic relationship of our gut microbiota, and in turn, contribute to our overall health. One of the most serious concerns about probiotics is the amount found in supplements. For a long time, it was assumed that the more bacteria found in a probiotic supplement, the more likely these bacteria will survive the journey to the gut microbiome and thrive in their new environment. However, the quantity may not be as important as the nutritional conditions that allow that bacteria to thrive once it reaches the gut. This is where the inclusion of prebiotics comes into play.

Prebiotics, a relatively new supplement on the market, have been recognized for their importance in sustaining and growing beneficial bacteria in the microbiome. Many fermented foods contain prebiotics, which are nutritional elements on which probiotics feed. A combination of prebiotics and probiotics increases the likelihood of beneficial bacteria thriving in the microbiome. Beneficial bacteria require nutrients that allow them to develop in order to multiply and remain in the gut. Prebiotics meet that nutritional requirement, resulting in stable and healthy gut microbiota.

Bacteriophages' distinct nature allows for a specific, non-invasive approach that contributes to the overall health of the gut microbiota and immune system. Lytic phages can be carefully chosen from phage libraries to target resistant bacteria known to invade and disrupt the human gut microbiota while leaving all other bacteria alone, with no known side effects to the body. Bacteriophages can also aid in the restoration of balance to the human gut microbiome caused by the pathogenic microbe.

Some complex supplements, such as Terraflora Advanced Care prepared by enviromedica (The phage has no association or affiliation with the enviromedica), are already on the market and claim to provide a three-pronged approach to stabilizing and maintaining a healthy gut microbiome. Bacteriophages that have been carefully selected target harmful gut bacteria, while probiotics introduce beneficial bacteria into the gut microbiota. Prebiotics provide enough nutrition for beneficial bacteria to survive and thrive in a healthy gut microbiome.

Phages are truly stunning, and the way they reproduce is fascinating. A phage binds to a bacterium and injects its DNA into the cell. The bacterium then transforms into a phage factory, producing up to 100 new phages before bursting and releasing the phages to attack other bacteria. This means that phages can multiply much faster than bacteria. Phages are used to treat bacterial infections in some countries, particularly in Eastern Europe. Because each phage can only infect and kill one type of bacteria, if a doctor knows which bacteria is infecting a patient, it may be possible to give the patient a phage that can infect and kill that type of bacteria.

References and credit:

enviromedica.com
Frontiers for Kids
Laboratory Insider