Question

From which bacterium the REN-Sal is isolated?
A. Escherichia coli
B. Streptococcus aureus
C. Haemophilus influenzae
D. Streptomyces albus

Answer 1

The restriction enzyme is a bacterial protein that cleaves DNA at specific locations. The restriction site is the name given to this location. They defend living bacteria from bacteriophages. They recognise and cleave at the bacteriophage's restriction sites, destroying its DNA. They are crucial genetic engineering tools. They can be separated from bacteria and employed in a laboratory setting.

Complete explanation:
Option A: The majority of Escherichia coli live in human intestines, where they aid in the digestion of food, as well as waste processing, vitamin K production, and food absorption.
So, option A is incorrect.
Option B: Streptococcus aureus has long been recognised as one of the most common bacteria responsible for human disease. It is the most common cause of abscesses (boils), furuncles, and cellulitis in the skin and soft tissues.
So, option B is incorrect.
Option C: Haemophilus influenzae causes pneumonia most commonly, but it can also cause more serious disorders such as meningitis and bloodstream infections. Haemophilus influenzae is a bacteria that can cause a variety of ailments.
Hence, option C is incorrect.
Option D: The enzyme Sal I was discovered in the Streptomyces albus bacteria. The first enzyme extracted from a bacteria is this one.
Option D is correct.

So, Option D is the correct answer.

Note:
Restriction enzymes identify recognition sequences in DNA, which are short and particular nucleotide sequences. When a restriction enzyme detects a DNA sequence, it cuts through the DNA molecule by hydrolyzing the link between adjacent nucleotides. With the help of enzyme methylases, the bacteria avoid the degradation of its own DNA sequences by adding a methyl group to the adenine or cytosine bases inside the recognition sequence. A gene is put into a plasmid during cloning. Single-stranded overhangs are created by restriction enzymes cutting the plasmid. With the help of DNA ligase, the two DNA molecules are ligated together to form a single DNA molecule.