bacteriophage t4 dna

Coli rna polymerase to dna of bacteriophage t4 is not measurably affected by uv doses up to approximately 1000 ergs mm 2.

Bacteriophage t4 dna. This dose is equivalent to about 150 lethal hits to t4vx harm 1963 or about 220 thymine dimers in the early region of the t4 genome. The t4 ligase is the most commonly used in laboratory research. The t4 phage releases enzymes that weaken the cell wall of the bacterium. Most phages range in size from 24 200 nm in length.

The genetic material of bacteriophage can be either dna or rna and linear or circular. The bacteriophage size ranges from 25 200 nm in length. A bacteriophage is essentially a virus consisting of dna or rna that is enclosed within a protein shell. This is a t4 bacteriophage virus.

Bacteriophage come in many different sizes and shapes. The basic structural features of bacteriophages are illustrated in figure 1 which depicts the phage called t4. It is approximately 200 nm long and 80 100 nm wide. Attached to this is the tail consisting of a tube like sheath and tail fibres at bottom.

It can ligate either cohesive or blunt ends of dna oligonucleotides as well as rna and rna dna hybrids but not single stranded nucleic acids. The t even phages t2 t4 and t6 were used as model systems for the study of virus multiplication. As a result there is an inverse correlation between genome size and per base mutation rate in dna viruses while the per genome mutation rate stays. The dna ligase from bacteriophage t4 a bacteriophage that infects escherichia coli bacteria.

The sheath then contracts injecting the contents of the head dna. The structure at top is the head which contains dna inside a protein coat. A bacteriophage is smaller than the bacteria. 2 shows binding of e.

The virus attaches itself to the host bacteria cell wall by its tail fibres. Some bacteriophages like the t4 bacteriophage that infects e coli also have a protein tail composed of fibers that help attach the virus to its host. In contrast the double stranded dna herpes simplex virus hsv and bacteriophage t4 both of which have genome sizes exceeding 150 kb show clearly lower mutation rates 10 8 10 7 m n c. Size t4 is among the largest phages.

Its genome size is about 49 kb. Bacteriophage can be either infectious or non infectious to the host cell. In 1952 alfred day hershey and martha chase used the t2 bacteriophage in a famous experiment in which they demonstrated that only the nucleic acids of phage molecules were required for their replication within bacteria. The results of the.