Respuesta :
The "scissors" of the molecular biology are: DNA Restriction enzymes.
A restriction enzyme is a protein capable of cleaving a DNA fragment at a characteristic nucleotide sequence called a restriction site. Each restriction enzyme thus recognizes a specific site. Several hundred restriction enzymes are currently known.
Naturally present in a large number of species of bacteria, these enzymes have become important tools in genetic engineering.
The "glue" of the molecular biology are: DNA ligase
In molecular biology, DNA ligases are ligase-class enzymes that catalyze the formation of a phosphodiester bond between two segments of DNA. DNA ligases are involved in several essential cellular processes of DNA metabolism: in DNA replication, suture of Okazaki fragments, and in DNA repair and homologous recombination.
The use of these tools in molecular biology: Cloning
Molecular cloning is one of the bases of genetic engineering. It consists of inserting a DNA fragment (called insert) in an appropriate vector such as a plasmid for example. The new plasmid thus created will then be introduced into a host cell, generally the Escherichia coli bacterium. This will then be selected and multiplied to obtain a large amount of the plasmid of interest. Cloning a gene involves inserting it into a plasmid. A clone will be the bacterial transformant that contains this particular plasmid. In this case we speak of clone because all the individuals of the bacterial colony are genetically identical. Molecular cloning is thus different from reproductive cloning (creating an individual genetically identical to another but of a different age) or therapeutic cloning (making tissues from stem cells to perform transplants compatible with the recipient).
Molecular cloning requires restriction enzymes capable of cleaving the DNA, and DNA ligase capable of re-gluing the DNA fragments. Ligase was isolated for the first time from T4 bacteriophage. This enzyme is involved in the repair and replication of DNA. It can bind DNA fragments with compatible sticky ends. At higher concentration, this enzyme is also able to bind two ends of DNA as shown here. T4 DNA ligase works using ATP and Mg ++. It has an activity optimum of 16 ° C, but remains active at room temperature.
The term scissors is used in molecular biology for an enzyme which is known as DNA restriction enzyme. The term glue is used in molecular biology for an enzyme which is known as DNA ligase. These enzymes are used for cutting and sticking the DNA during recombinant DNA technology.
Further Explanation:
Restrictionenzymes commonly known as the scissors in the molecular biology are the enzymes that are used to cut the DNA into smaller parts for cut the DNA from a target sequence. There are enzymes that act as molecular scissors and cut the DNA with overhanging strands. These strands are known as sticky ends. There are also the enzymes that cut the DNA with blunt ends and these ads are known as blunt ends. Restriction enzymes predominantly used in a molecular biology or recombinant DNA technology lab. EcoR1 is the most common example of a restriction enzyme.
DNA ligase commonly known as the molecular glue is used to stick the strands of DNA that are cut by the help of restriction enzymes. A single piece of DNA is formed by sealing the gap between the molecules which is only possible with the help of DNAligase.
Both these enzymes are widely used in the recombinant DNA technology laboratory for the cutting of specific part of DNA and the insertion of intended genes into the plasmid during DNA cloning.
Learn more:
1. Learn more aboutstructural component is found in DNA: https://brainly.com/question/334927
2. Learn more about DNA: https://brainly.com/question/2416343
3. Cell cycle and DNA replication: https://brainly.com/question/1600165
Answer Details:
Grade: High School
Subject: Biology
Chapter: Molecular Biology
Keywords:
Molecular scissors, molecular glue, restriction enzyme, DNA ligase, DNA strand, plasmid, DNA cloning, recognition sites, sticky ends, blunt ends.
