Titer Bacteriophage

The titer of a bacteriophage is an important indicator of its effectiveness in combating bacterial infections. It reflects the number of active bacteriophage units in one milliliter of phagolysate.

There are two main methods for determining bacteriophage titer:

1. According to Appelman. This method is based on determining the maximum dilution of a bacteriophage suspension, which can cause lysis of sensitive bacteria in a liquid medium. To do this, the material under study is placed in a test tube with a liquid medium containing sensitive bacteria. Then the phage is serially diluted and added to the test tube with the bacterial culture. After incubation for a certain time, the results are assessed - if lysis of bacteria is observed, then the titer of the bacteriophage is considered certain.

2. According to Grazia. This method consists of determining the number of negative colonies that are formed from a certain volume of bacteriophage suspension when it is co-cultivated with sensitive bacteria in a liquid medium. Test tubes with a bacterial culture and the test material are placed in a thermostat for a certain time. Then the number of negative colonies is counted and compared with the bacteriophage titer using the formula: number of negative colonies = bacteriophage titer x 100.

Depending on the purpose of the study and the methods used, the bacteriophage titer can be determined for one strain of bacteria or for several strains. This indicator is an important criterion when choosing antibacterial therapy and assessing the effectiveness of treatment of bacterial infections.

Nowadays, bacteriophages are one of the most important and widely studied objects of modern biology. Bacteriophages are viruses that can infect and parasitize certain bacterial cells called hosts. However, their role in biochemistry has also become the focus of research due to the fact that they can be useful for studying processes associated with bacterial development. Bacterial infections with bacteriophilic viruses are considered to be a multistage process associated with certain stages of host growth and target damage.

The titer of bacteriophages can be determined in various ways and is often one of the key parameters in studies devoted to the study of these viruses. One of the determination methods is titers using the Appelman method, which is based on the use of certain volumes of phage suspension subjected to cell lysis in a liquid medium. In this case, phages can detect lysis properties, as well as the ability to pass through the membranes of bacterial cells in order to penetrate them and cause destruction of the cell wall.

In addition, the use of Appelman's method makes it possible to determine the number of phage particles formed as a result of this procedure. This is known as the Apfelmann titer and can be measured by comparing the size and amount