t4 bacteriohage

short presentation

1. A presentation on T4 bacteriophage Md. Adnan Munim ASH1513047M Dept. of Biotechnology And Genetics Engineering Noakhali Science and Technology University

2. T4 bacteriophage Introduction Characteristics Structure Life cycle & viral infection The role of bacteriophage t4 in cholera and diphtheria Significance

3. Assalamualaikum mam good morning to everyone. It is honour to me to present here something and thank you mam for that I want to prenent the t4 bacteriophage on this day

4. I ntroduction Virus is an infective agent that typically consists of a nucleic acid molecule in a protein coat, and is able to multiply only within the living cells of a host. Viruses have few or no enzymes of their own they d on’t contain Ribosome . To multiply, viruses must take over the metabolic machinery of the host cell. That’s why they are called obligatory intracellular parasites. Viruses had infected bacteria are known as bacteriophage (from the Greek “to eat bacteria”). Bacteriophage T4 is a virulent phage. It is also known as lytic phage.

5. Characteristic Bacteriophage T4 (phage T4) is a virulent phage; it uses the metabolic machinery of the host cell to produce progeny viruses and kills the host in the process. Bacteriophage T4 is a large & dsDNA virus. T4 bacteriophage infect the colon bacillus Escherichia coli bacteria . it does not have a probacteriophage form , The T4 chromosome is approximately 168,800 base pairs long and contains about 150 characterized genes.

6. Structure Large virus with a complex protein coat –At least 36 different types of proteins make up the coat Over 150 genes, 189 kb genome of ds DNA The tail has an inner hollow tube called core, surrounded by a contractile sheath which consists of 24 annular rings. The distal end of the tube is connected to a hexagonal basal plate with spike or tail spin at each corner. Six long, flexible tail fibers also arise from the basal plate.

7. Life cycle &viral infection in E.coli

8. The role of bacteriophage t4 in cholera and diphtheria Cholera is caused by the bacterium  Vibrio cholera.  However,  V. cholera does not cause the disease unless it is infected with a lysogenic T4 bacteriophage carrying the gene for cholera toxin. Cholera toxin is what causes the severe diarrhea . Corynebacterium diphtheriae ,  the bacterium that causes diphtheria.  must carry a phage containing the gene for diphtheria toxin to cause the disease.

9. Significance Phages may be useful in killing bacteria that are resistant to antibiotics or in cases where the antibiotic has difficulty in reaching the bacteria phages are specific—a specific phage will only kill a few strains of bacteria. Thus, they leave the native bacteria flora intact . T4 bacteriophage also use in the Recombinant DNA Technology. In the past, phages were also used by some to treat infections.

10. Thankyou