Gene technology

Gene Technology

The direct manipulation of an organism's genes using biotechnology to change the genetic makeup of cells.

Recombinant DNA

The altered DNA resulting from the genetic engineering process, involving the transfer of genes within and across species boundaries.

Restriction Enzymes

Proteins produced by bacteria that cleave DNA at specific sites, creating blunt ends or sticky ends.

Southern Blotting

A technique to detect specific DNA sequences by transferring DNA fragments to a membrane and using probes for hybridization.

Polymerase Chain Reaction (PCR)

A method to amplify DNA segments using thermal cycling with denaturing, annealing, and extending stages.

Plasmid

A carrier DNA molecule, often a bacterial plasmid, used to insert foreign DNA for gene expression.

Recombinant DNA Technology Steps

The process involving identifying genes, cloning DNA, inserting DNA into vectors, transferring vectors into host cells, and harvesting desired proteins.

Plasmid Uptake in Bacteria

Bacteria like E.coli can take up plasmids in the presence of calcium ions, which increase cell wall permeability, allowing plasmids to enter the cytoplasm.

Sticky Ends in Recombinant DNA

Cut plasmids and gene fragments with complementary sticky ends can reanneal without incorporating the desired gene, affecting transformation efficiency.

Marker Genes in Genetic Modification

Antibiotic resistance genes are used as markers to identify genetically modified host cells carrying recombinant DNA plasmids.

pBR322 Plasmid

A vector containing genes for resistance to ampicillin and tetracycline, used in genetic engineering to select bacteria with the desired gene.

Replica Plating Technique

A method to identify bacteria with recombinant plasmids by transferring colonies from an antibiotic-containing plate to another to observe antibiotic resistance patterns.

Gene Marker Concerns

Antibiotic resistance genes as markers pose risks of transferring resistance to pathogenic bacteria, leading to the development of alternative markers like GFP and GUS.

Cloning and Protein Harvesting

Selected bacterial colonies with recombinant plasmids are grown in fermenters to produce desired proteins like insulin for extraction and purification.