Staphylococcus aureus and staphylococcal bacteriophage from 2D to 3D

Competition “Bio/Mol/Text”-2020/2021

This work was published in the nomination “Visually about the beloved” of the competition “Bio/Mol/Text”-2020/2021.

The general partner of the competition is the annual biotechnology conference BiotechClub, organized by the international innovative biotechnology company BIOCAD.

The sponsor of the competition is SkyGen: a leading distributor of life science products on the Russian market.

Competition sponsor: the largest supplier of equipment, reagents and consumables for biological research and production.

"Book" sponsor of the competition - "Alpina Non-Fiction"

A little about VR

There is a part in the video where VR work is presented. To better understand what is where, please read the description below:

1. For ease of viewing the internal processes occurring in a bacterial cell, the cell wall and cytoplasmic membrane are made transparent.
2. In the virus reproduction cycle, one type of bacteriophage is considered. This is staphylococcal bacteriophage 80α (alpha).
3. The processes of replication, translation and transcription are simplified, and for a better visualization of these processes they are slightly separated in space.

Staphylococcus aureus

Staphylococci are gram-positive and non-spore-forming cocci that form pairs, short chains or clusters. The genus Staphylococcus contains many species that are separated from each other based on the production of the enzyme coagulase [1].

Staphylococcus aureus (Staphylococcus aureus) is a coagulase-positive species and is one of the most virulent species.

Virulence (from Latin virulentus - “poisonous”) the degree of ability of an infectious agent (strain of microorganism or virus) to cause disease or death of the body.

Staphylococcus aureus is an often harmless inhabitant of the epithelium of human skin and mucous membranes, but is also associated with serious systemic and local infections [2] and is one of the most common causes of foodborne infections worldwide. S. aureus produces 15 enterotoxins.

Enterotoxins are bacterial toxins that cause the secretion of fluid from intestinal cells.

Fighting Staphylococcus aureus

The fight against bacteria has been going on for a long time. People have tried to treat wounds with plants. And by trial and error, the necessary antimicrobial drugs were selected [3].

However, the real fight against bacteria began with the discovery of penicillin by Alexander Fleming in 1928. And already in 1929, Fleming’s article was published in the British Journal of Experimental Pathology. Although penicillin had already been “discovered” several times before Fleming, scientists of that time only wrote reports, took notes, but did not publish the results in scientific journals [4]. The open mushroom killed staphylo- and streptococci and even diphtheria bacillus [5].

Already in 1940, the first information about bacterial resistance to penicillin appeared.

Bacteriophage staphylococcal liquid 100ml fl vn

Directions for use and dosage: The drug is approved for use in newborns and children of all ages. The drug is injected into the site of infection. The frequency of injections and their size are determined by determining the clinical form of the disease, the nature of the infectious focus and standard recommendations. The average duration of treatment is 5-15 days. In cases of relapse, additional courses of treatment are possible. Instructions for using staphylococcal bacteriophage for children and adults are somewhat different. Recommendations for the use of the drug for children are given at the end of the section.

Liquid phage is allowed to be used topically in the form of lotions, irrigation or tamponing in a volume of up to 200 ml, taking into account the size of the affected area. An ointment is also available for topical use.

It is advisable to carry out therapy of purulent-inflammatory limited lesions both locally and orally for 1-4 weeks.

For purulent-inflammatory lesions of the throat, ear or nose, the drug is used for rinsing, instilling, washing and administering moistened turundas 2-10 ml up to three times a day.

For carbuncles and boils, liquid bacteriophage is injected directly into or around the lesion, 0.5-2 ml daily. In total, up to 5 injections are given per course of treatment.

Treatment of chronic osteomyelitis is carried out by infusion of the drug into the wound immediately after surgical treatment.

In case of abscesses, the bacteriophage is injected into the cavity of the lesion, emptied of pus. When opening an abscess, a tampon moistened with the drug is inserted into the wound.

Treatment of deep pyodermatitis is carried out by making intradermal injections of the drug into one place of 0.1-0.5 ml or into several places in a total dose of up to 2 ml. Administration is carried out every 24 hours, a total of 10 injections.

For administration into the abdominal, pleural, and articular cavities, capillary drainage is used, and up to 100 ml of bacteriophage is injected every other day. There are only 3-4 such introductions.

For cystitis, the drug is injected into the bladder using a catheter.

For purulent bursitis, pleurisy or arthritis, the drug is administered into a cavity previously emptied of pus, 20 ml every other day. The course of treatment is 3-4 administrations.

Also, Staphylococcal bacteriophage is used orally in the form of tablets in the treatment of urogenital infections (cystitis, pyelonephritis, pyelitis, salpingoophoritis, endometritis), intestinal infections and other diseases caused by staphylococcus.

How to use Staphylococcal Bacteriophage for intestinal staphylococcal lesions and intestinal dysbiosis: the drug is used orally on an empty stomach three times a day, 2 hours before meals; The drug is prescribed rectally in the form of suppositories or enemas once a day. Treatment lasts 7-10 days.

Bacteriophage

In 1919, even before the discovery of penicillin, Felix D'Herelle discovered a completely different method of combating bacteria. But then he was never able to compete with antibiotics. We are talking about bacteriophage therapy.

Bacteriophages (phages) are viruses that use only prokaryotic cells to reproduce. These viruses are found everywhere in nature [6]. S. aureus was one of the first organisms used to demonstrate the existence of a bacteriophage [2].

In the 1920s–1940s, many studies were carried out on the clinical use of bacteriophages, but no consistent results were obtained. In the West, they began to abandon bacteriophage therapy [7].

The fight between Staphylococcus aureus and bacteriophage

Now phage preparations are mixtures of several bacteriophages. We will focus on one of the staphylococcal phages.

Phage 80α is a temperate lambda bacteriophage of the family Siphoviridae with a double-stranded DNA genome. 80α is capable of generalized transduction and may also act as a facilitator for the mobilization of SaPI pathogenicity islands [2], which have been shown to encode virulence factors such as toxic shock syndrome toxins and coagulase [1].

Like other bacteriophages, the 80α capsid assembles as an empty precursor, the procapsid. Handfuls of phage DNA are packaged into procapsids through the portal apex in an ATP-dependent process that requires small and large subunits of the terminase enzyme. DNA packaging is accompanied by expansion of the capsid and structural rearrangement of the shell.

For bacteriophage therapy, it is recommended to use those bacteriophages that follow the lytic path of development (with cell rupture).

Bacteriophage preparations

Now, with the development of modern methods of genetic engineering and molecular biology, bacteriophage therapy is coming to life in new research. And at the moment, bacteriophage therapy is used very carefully and strictly controlled, in order to avoid repeating the story with antibiotics.

However, such strict standards are not observed everywhere. In Western Europe, after the discovery of antibiotics, the use of bacteriophages was quickly abandoned. In Eastern Europe, despite the lack of large and well-controlled clinical trials, they remained a relatively popular treatment into the 20th century [8].

In the USSR, the study of bacteriophages continued. This led to the accumulation of a large collection of them in the countries of the post-Soviet space. Now, when Western countries are just beginning to take a closer look at bacteriophage therapy for the treatment of Staphylococcus aureus and prescribe them to a sick person in rare cases under the strict supervision of a doctor [9], in Russia bacteriophages are used quite actively as a medicine. And they can prescribe such drugs “lightly” despite the fact that their effectiveness has not been proven [10–16]: most Russian studies of bacteriophages are limited to 30–40 participants - such studies are not evidence-based. Unfortunately, such careless use of drugs can lead to an increase in bacterial resistance.

It is very important to treat bacteriophages with extreme caution. Otherwise, we will soon see the news “Bacteria are resistant to bacteriophage therapy.”

Staphylococcal bacteriophage (Bacteriophagum Staphylococcum)

The drug is used for oral administration (oral), rectal administration, applications, irrigation, administration into wound cavities, vagina, uterus, nose, sinuses and drained cavities. Before use, the vial with the bacteriophage must be shaken and inspected. The preparation must be transparent and free of sediment.

Treatment of purulent-inflammatory diseases with localized lesions should be carried out simultaneously both locally and by taking the drug orally 2-3 times a day on an empty stomach 1 hour before meals from the first day of the disease for 7-20 days (according to clinical indications).

If chemical antiseptics were used to treat wounds before using the bacteriophage, the wound should be thoroughly washed with a sterile sodium chloride solution of 0.9%.

Depending on the nature of the source of infection, the bacteriophage is used:

1. In the form of irrigation, lotions and tamponing in a volume of up to 200 ml, depending on the size of the affected area. In case of an abscess, after removing the purulent contents using a puncture, the drug is administered in an amount less than the volume of the removed pus. In case of osteomyelitis, after appropriate surgical treatment, 10-20 ml of bacteriophage is poured into the wound.
2. When administered into cavities (pleural, articular and other limited cavities), up to 100 ml, after which capillary drainage is left, through which the bacteriophage is administered for several days.
3. For cystitis, pyelonephritis, urethritis, the drug is taken orally. If the cavity of the bladder or renal pelvis is drained, the bacteriophage is injected through the cystostomy or nephrostomy 1-2 times a day, 20-50 ml into the bladder and 5-7 ml into the renal pelvis.
4. For purulent-inflammatory gynecological diseases, the drug is administered into the vaginal cavity, uterus in a dose of 5-10 ml once daily, for colpitis - 10 ml by irrigation or tamponing 2 times a day. Tampons are placed for 2 hours.
5. For purulent-inflammatory diseases of the ear, throat, nose, the drug is administered in a dose of 2-10 ml 1-3 times a day. The bacteriophage is used for rinsing, washing, instilling, introducing moistened turundas (leaving them for 1 hour).
6. For enteral infections and intestinal dysbiosis, the drug is taken orally 3 times a day 1 hour before meals. It is possible to combine double oral administration with a single rectal administration of a single age-specific dose of the bacteriophage in the form of an enema after bowel movement.

Use of bacteriophage in children (up to 6 months).

For sepsis and enterocolitis in newborns, including premature babies, the bacteriophage is used in the form of high enemas (through a gas tube or catheter) 2-3 times a day in a dose of 5-10 ml. In the absence of vomiting and regurgitation, it is possible to use the drug by mouth. In this case, it is mixed with breast milk. A combination of rectal (in the form of high enemas) and oral (through the mouth) use of the drug is possible. The course of treatment is 5-15 days. In case of recurrent course of the disease, repeated courses of treatment are possible. In order to prevent sepsis and enterocolitis during intrauterine infection or the risk of nosocomial infection in newborns, the bacteriophage is used in the form of enemas 2 times a day for 5-7 days.

In the treatment of omphalitis, pyoderma, and infected wounds, the drug is used in the form of applications twice daily (a gauze pad is moistened with a bacteriophage and applied to the umbilical wound or to the affected area of ​​the skin).