The substrates bind to a region on the enzyme called the active site. The active site is precisely shaped to hold specific substrates. Beta-galactosidase is one of the three genes in the lac operon. A lac operon is an operon required for the digestion of lactose in bacteria cells. B-galactosidase converts lactose, a disaccharide, into glucose and galactose, monosaccharides.
Regulation of trp and ara operon trp operon: The trp operon is a group of genes that are used, or transcribed, together that codes for the components for production of tryptophan. The trp operon is present in many bacteria, but was first characterized in Escherichia coli. The operon is regulated so that when tryptophan synthesis are not expressed. It was an important experimental system for learning about gene regulation, and is commonly used to teach gene regulation.
Throughout the urea cycle, the amino acid, arginine, is changes into ornithine- this is another amino acid when hydrated, that is when water was added. During this reaction, urea is the product formed (Nelson and Cox 2008). Figure 1 shows the urea cycle, occurs specifically in the mitochondria and cytosol in the liver. (Nelson and M.Cox 2008). Urea is made in the liver by means of enzymes in the urea cycle.
We now know that HGD gene consists of 14 eons (which are the coding parts of the gene) and 13 introns (which are the non-coding parts of the gene). The HGD gene has a tissue specific expression, particularly in the liver, kidneys, small and large intestines, prostate and the brain. Increased activity in the liver and kidneys has been attributed to metabolic activity of these organs in the
Which of the following is the appropriate prefix to measure the amount of space taken up? A. Mili B.Deca C.Kilo D.Micro 38. In addition to oxygen and carbon dioxide, the circulatory system is the primary delivery system for? A.cerebrospinal fluid B.exocrine secretions C.biliary fluids D.endocrine hormones 39.
Additionally, there exists three domains of the enzyme namely C- terminal catalytic domain, an N- terminal regulatory domain and a tetramerization domain. Tetrahydrobiopterin (BH4) acts as a cofactor for the enzyme activity. Hence, the regulatory action by PAH enzyme involves activation by the presence of the amino acid phenylalanine, inhibition by the cofactor Tetrahydrobiopterin (BH4) and activation of the enzyme by phosphorylation. Cyclic adenosine monophosphate (cAMP) – dependent protein kinase helps in the phosphorylation of the amino acid serine that is present on the 16 position of the regulatory domain of the enzyme. This in turn helps in maintaining the activity of the enzyme by reducing the concentration of the phenylalanine
This experiment involved the chosen enzyme, B-Galactosidase, to be tested with a substrate called o-nitrophenol-B-D-galactopyranoside (ONPG). The purpose was to determine over time the effects the enzyme had on the substrate concentration, as well as to examine the effect of lactose, a disaccharide on the formation of o-nitrophenol. The experiment utilized a spectrophotometer to determine at which the rate that the enzyme catalyzes, by timing the change in absorbance every 15 seconds, as well as observing any colour change. The amount of enzyme added to the B-Galactosidase is increased over time, and the ONPG is set to a constant value each trial. It was determined that through the trials of testing the absorbance of the enzyme, the faster
Materials and methods Isolation and identification of Bacillus thuringiensis Bacillus thuringiensis was isolated from raw milk (Taif, KSA) on nutrient agar at 37oC for overnight. The supernatant of the bacterial isolate was screened for synthesis of AgNPs. The bacterial isolate was morphologically and biochemically characterized according to Bergy’s Manual of Systemic Bacteriology. Also, this bacterial isolate was further identified by 16S rRNA sequencing.
This enzyme acts as an escort for ubiquitin to its next destination E3 ligase enzyme. E2 ubiquitin conjugating enzyme Figure 16: Schematic representation of transfer of activated Ubiquitin from E1 activating enzyme to E2 conjugating enzyme The E3 enzyme act as a platform on which the target protein substrate and the active E2 ubiquitin complex can meet and interact. The E3 enzyme is extremely fussy about exactly which E2 enzyme and which protein can interact.
Squalene undergoes a two-step cyclization to yield lanosterol catalyzed by sequalene mono-oxygenase and sequalene 2, 3 epoxidase enzymes. Sequalene mono oxygenase is the second committed step in cholesterol biosynthesis and lead to the formation squalene 2, 3 epoxide. This enzymatic reaction require supernatant protein factor (SPF) and NADPH as a cofactor to introduce molecular oxygen as an epoxide at the 2, 3 position of squalene. The activity of supernatant protein factor itself is regulated by phosphorylation/dephosphorylation (Singh et al., 2003). Through a series of 19 additiona lreactions, lanosterol is converted to cholesterol.
chinesis. A construct of R751::Tn4351 (the physical map of R751::Tn4351 and restriction sites are shown in fig. 7) was selected for introduction into F. chinesis to discover if the introduction and insertion of the vector R751 and the transposition of T4351 into the F. chinesis chromosome by a triparental mating occurred. One parent was E. coli GJ342 which carried a helper plasmid, the second parent was E. coli HB101 which contained R751::Tn4351 and the third parent was the F. chinesis target strain. 189 colonies were isolated on LB agar plates which in passage in fresh media were able to grow in 200µgml-1 erythromycin.
Transformation in bacteria usually takes place when a bacterial cell accepts strange DNA and integrates to its own DNA. The transformation normally takes place within plasmids, which are tiny circular DNA molecules that have been separate from its own chromosome. The copies of the same plasmid range from 10 to 200 copies within a cell. These copies of plasmids may multiply when the chromosome replicate or multiply independently. One plasmid has a range of 1,000 to 200,000 base pairs.