Question

1. Describe the gene and protein E. coli beta-glucuronidase. What is its biological function?

2. Describe the pET28a plasmid.  

Answer 1

Answer 1 :- β-glucuronidase is a glycosyl hydrolase which hydrolyses β-glucuronic acid residues from the glycosaminoglycan (GAG) non-reduction termini. β-glucuronidase (GUS) protein sequences from prokaryotes and eukaryotes are available from NCBI GenPept. The Escherichia coli GUS is a well-researched glycosyle hydrolase in prokaryotes. The coli β-glucuronidase gene (uidA) was sequenced, and it is known to encode a stable enzyme. I. E. Coli GUS is 603 long amino acid residues and shares approximately 50 per cent of the identity of the human GUS sequence with the same specificity of the substrates.
β-glucuronidase is a widespread enzyme present in many organisms, including animals and several bacterial species. This enzyme catalyzes a glucuronide group's hydrolytic cleavage from substrates into forming glucuronic acid and organic alcohol.

A gene is the fundamental unit of heredity, physical and functional. Genes are produced by DNA. Some genes serve as instructions for producing proteins, called molecules. Each individual has two copies of each gene, one of which is inherited from each parent. Genes are a series of instructions that decide how the organism is, how it feels, how it lives, and how it conducts in its environment. Genes are made from a material called deoxyribonucleic acid, or DNA. They offer instructions to create the molecules called proteins for a living being.

Answer 2 :-

epitope tag, C-terminal His tag; kanamycin resistance; enzyme restriction cloning. Uses the promoter host lacUV5 caused by IPTG binding the lac repressor and promoter site and promotes transcription of T7 RNA polymerase. The inserted gene is then cloned within the read frame with a T7 promoter inside the plasmid.