1) Alcaligenes faecalis is a Gram-negative coccobacilli that is motile, oxidase positive, catalase positive, non-spore-forming, non-fermenting, slow growing, and citrate positive obligate aerobe (Mahon et al., 2014) (Sachdeva et al., 1963). Its colony morphology is flat, thin, and rough with irregular edging (Mahon et al., 2014) and the flagella varies between the usual shape versus the curly structure, however, both shapes do not exist on the same individual bacteria (Leifson, 1960). The bacteria is most commonly found in watery environments (Bizet et al.,1997) however, it was sequestered in 1896 by Petruschky from stale beer (Desai, 1960). The species’ name originates from the initial discovery in feces. Nevertheless, it was later established
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This plasmid is a circular DNA molecule that is commonly used as a cloning vector with E.coli (Ke et al., 2008). This plasmid has been engineered to include a unique feature of a gene that codes for antibiotic resistance to ampicillin, an antibiotic that inhibits the synthesis of the cell wall which in result, destroys the cell. This is prevented with the resistance coded gene called β-lactamase, which breaks down the ampicillin prior to it preventing cell wall synthesis. The vector length is 2686 bp with a copy number range of 500-700 per bacterium. To selectively grow bacteria that have been successfully injected with the pUC18 plasmid DNA, it would have to be done in a media containing ampicillin so that the bacteria that do not contain the gene will not be able to survive thus leaving only the ones containing the gene. This screening process of the transformed bacterial colonies will distinguish the surviving bacteria’s. Although, some bacteria’s are able to generate recombinant plasmids, others are able to reform their DNA without the foreign DNA insert to which thereby causes a mixture of the recombinant plasmids and the plasmids that do not contain the insert. To signify which ones have the inserted DNA, the blue-white screening technique must be used. This method presents the DNA that have been inserted into the plasmid which interrupts the lacZ gene, thereby preventing the α peptide from being produced. As a …show more content…
Genentech first produced recombinant human insulin in E. coli in 1978 (Chance et al., 1993). Using an approach that required the expression of chemically synthesized complimentary DNA, it was able to code for the insulin A and B chains created separately in E. coli (Chance et al., 1993). Once expressed, the two chains are then purified and co-incubated for productive generation of bioactive insulin via disulphide bond formation (Chance et al., 1993). An alternative approach encompasses the expression of a single synthesized complimentary DNA encoding for human proinsulin in E. coli followed by purification and subsequent excision of C-peptide by proteolytic digestion (Chance, 1999). In short, similar to the genetic modification process done in this lab, the insertion of a particular coding plasmid allows the host organism to acquire new properties and
This plasmid is a circular DNA molecule that is commonly used as a cloning vector with E.coli (Ke et al., 2008). This plasmid has been engineered to include a unique feature of a gene that codes for antibiotic resistance to ampicillin, an antibiotic that inhibits the synthesis of the cell wall which in result, destroys the cell. This is prevented with the resistance coded gene called β-lactamase, which breaks down the ampicillin prior to it preventing cell wall synthesis. The vector length is 2686 bp with a copy number range of 500-700 per bacterium. To selectively grow bacteria that have been successfully injected with the pUC18 plasmid DNA, it would have to be done in a media containing ampicillin so that the bacteria that do not contain the gene will not be able to survive thus leaving only the ones containing the gene. This screening process of the transformed bacterial colonies will distinguish the surviving bacteria’s. Although, some bacteria’s are able to generate recombinant plasmids, others are able to reform their DNA without the foreign DNA insert to which thereby causes a mixture of the recombinant plasmids and the plasmids that do not contain the insert. To signify which ones have the inserted DNA, the blue-white screening technique must be used. This method presents the DNA that have been inserted into the plasmid which interrupts the lacZ gene, thereby preventing the α peptide from being produced. As a …show more content…
Genentech first produced recombinant human insulin in E. coli in 1978 (Chance et al., 1993). Using an approach that required the expression of chemically synthesized complimentary DNA, it was able to code for the insulin A and B chains created separately in E. coli (Chance et al., 1993). Once expressed, the two chains are then purified and co-incubated for productive generation of bioactive insulin via disulphide bond formation (Chance et al., 1993). An alternative approach encompasses the expression of a single synthesized complimentary DNA encoding for human proinsulin in E. coli followed by purification and subsequent excision of C-peptide by proteolytic digestion (Chance, 1999). In short, similar to the genetic modification process done in this lab, the insertion of a particular coding plasmid allows the host organism to acquire new properties and