Question

Resistance towards first line antibiotics by MRSA is a big problem. Explain what temperate and lytic phages are, how they infect enteric bacteria, and how it may be used in a treatment of new phage therapy as a potential way to target specific pathogens.

Answer 1

Temperate Phage: The bacteriophages that integrates its genome to the bacterial genome and remains in latent phase and undergoes replication along with bacteria are the temperate phages. However when the bacteria is under stress or the conditions are unfavourable they can disintergrate from the bacterial chromosome and lyse the bacteria.

Lytic Phages: Lytic bacteriophages enter into the bacteria repilicate and assemble themselves inside thebacteia using host machinery and gets out by lysis of bacterial cell. They do not integrate with the bacterial genome.

MSRA are Methicillin resistant Staph. aureus. These bacteia have resistance against the commonly used antibiotics. Bacteriophages are very specific to their host bacteria. Bacteria generally do not have resistance to Phages (though exceptions are there). So by using them as therapeutic is a potetial way to eliminate drug resistant pathogens. Phages are engineered such that they can infect the bacteria once and can replicate and lyse them, but they can not reinfect other cells. These are known as replication incompetent bacteria.