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Griffith’s experiment was a stepping stone toward the future discovery of genetic material. The bacteria Streptococcus pneumoniae was used in the Frederick Griffith experiment. Griffith cultured bacteria from the bacterium Streptococcus pneumoniae, which grew in two distinct patterns during the experiment.
The Griffith Experiment
In 1928, English bacteriologist Frederick Griffith published “Griffith’s Experiment,” which described the transformation of a non-pathogenic pneumococcal bacteria into a virulent strain. 17 Griffith combined live non-virulent bacteria with a heat-inactivated virulent type in this experiment. He then infected mice with this concoction, and the mice developed pneumonia and died, much to his amazement. He was also successful in isolating colonies of the virulent strain from these mice. He reasoned that the non-virulent strain had converted into the virulent variety because the original virulent strain had been heat-inactivated.
This phenomenon was originally noticed, but Dawson and Sia, who were also able to execute this change in vitro, confirmed it a year later. 18 James L. Alloway continued Dawson’s research and took the experiment a step farther. He extracted a cell-free extract by lysing the pathogenic bacteria strain and filtering the intracellular material. He noticed that even this extract changed the non-virulent strain into a virulent one, and he theorized that something in the cell-free extract was responsible for this transformation.
Avery and his colleagues had to extract and purify proteins, DNA, RNA, and other biomolecules from heat-killed S strain bacteria. According to their findings, DNA is the genetic material and is the only factor responsible for the transformation of the R strain bacteria. Proteases and RNA-digesting enzymes (RNases) had no effect on transformation, whereas DNase had an inhibitory effect. Despite the fact that it was not universally accepted, they came to the conclusion that DNA was genetic material.
The Functions of DNA With the exception of RNA viruses such as HIV, which contain RNA, DNA is the genetic material of all living organisms. It is the world’s largest super chip and can store massive amounts of data in a small amount of space.
The DNA within the zygote contains all of the information required for the zygote to develop into an individual organism.
An individual’s physical characteristics, such as the shape of their eyes, ears, nose, and skin colour, as well as their longevity, ability to withstand stress, and the presence of certain congenital diseases such as diabetes and hypertension, are determined by the DNA that they inherit from their parents. The DNA of a cell is the source of information used to synthesise all of its proteins. A gene is a segment of DNA that contains instructions on how to make a protein.
Ribonucleic acids (RNA) are single-stranded nucleic acids with the sugar ribose. RNAs are the second most abundant type of nucleic acid in the cell, and they are made up of nucleotides with ribose as their sugar. RNA is important in protein synthesis in the body because it aids in the transfer of information from the nucleus to the cytosol, decoding, and protein synthesis. RNA nucleotides are composed of three distinct parts.
Nucleic Acids (NA): Phosphate Group, Nitrogenous Base, and Ribose Sugar
Among the nitrogenous bases are adenine (A), guanine (G), cytosine (C), and uracil (U) (U).
Through base pairing within the strand, the single-stranded RNA molecule can form three-dimensional structures such as hairpin loops. In the nucleotide sequence, adenine is paired with uracil (A=U), and guanine is paired with cytosine (G=C). In this case, RNA does not follow Chargaff’s rule.
Types of RNA molecules
There are three types of RNA molecules, which are found in all prokaryotic and eukaryotic cells. They are a group of individuals (1). The term mRNA (messenger RNA) refers to a type of RNA that communicates with other RNAs (mRNA). (2). tRNA (transfer RNA) is a type of RNA (3). RNA discovered in ribosomes (rRNA). They are distinct in terms of size, shape, formation, and stability.
Conclusion:
As a result of his observations, Griffith concluded that R strain bacteria had been transformed by S strain bacteria. The R strain bacteria were virulent because they inherited a ‘transforming principle’ from the heat-killed S strain bacteria. And he regarded this transforming principle as a type of genetic material.
