Why is IPTG a more effective inducer for the lac operon compared to lactose?
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IPTG is a substituted galactoside, where the glucose moiety of lactose is replaced by another chemical group.IPTG binds to repressor and inactivates it, but is not a substrate for β-galactosidase enzyme. IPTG is an effective inducer because of the following reasons: \n1.One advantage of IPTG for in vivo studies is that it cannot be metabolized by E. coli, therefore the growth rate of cells (usually maintained with glycerol as the carbon and energy source), is not a variable in the experiment.\n\n2. IPTG is not dependent on permease to enter the cell and is not cleaved by ßgalactosidase.So it is transported efficiently independent of whether the lacY gene is functional. And since cells don't metabolize IPTG, its concentration doesn't change during the course of an experiment.
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Yes, try to this!\n\nhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=3906008
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What a wonderfully esoteric question!  I've been able to find one site (or a doc on a site) that says,\n\n"The effective spring constant of the DNA is 0.073 pN/nm .."\nhttp://picasso.ucsf.edu/~mollyd/ProblemSet2.doc\n\nBut, I don't know if this will meet your needs.  Here's my search terms.  Maybe you can browse these hits and see if something is more appropriate.\n\nhttp://www.google.com/search?q=dna+%22spring+constant%22+pN/nm+&hl=en&lr=&rls=GGLJ,GGLJ:2006-08,GGLJ:en&start=30&sa=N
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Using the Michaelis-Menten equation.\n\nMore details on teh attached link\n\nhttp://www.le.ac.uk/by/teach/biochemweb/tutorials/michment2print.html\n\nGood luck
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Prokaryotic  proteins -\n1. Cro and repressor proteins\n2. LacI purine repressor proteins (PurR)\n3. FokI restriction endonuclease (DNA-recognition region)  \n4. Gamma-delta recombinase protein \n5. Hin recombinase protein\n6. Trp repressor protein \n7. Diptheria tox repressor \n8. Catabolite gene activator proteins (CAP)   \n\nEukaryotic proteins -\nHomeodomain proteins \n2. RAP1 protein \n3. Prd paired protein  \n4. Tc3 transposase protein \n5. TFIIB family  \n6. Interferon regulatory factor \n7. Transcription factor family \n8. ETS domain family \n9.TATA Box-Binding Proteins \n\nThese are some protiens associated with DNA
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Hi, i've read of an article about microbiology and genetic engineering; to sum it up, here goes:\nIn recent years, bacteriology has been greatly expanded from its concentration on bacterial disease. The discovery that bacteria fix nitrogen in the root nodules of leguminous plants (see Nitrogen Fixation) has led to attempts to inoculate the roots of other plant strains and thereby increase soil fertility and the productivity of food crops. Some bacteria are able to digest petroleum and other hydrocarbons; others absorb phosphorus. These bacteria are being intensively investigated as possible aids in cleaning up oil spills and removing phosphorus from sewage sludge. Other bacteria may be more efficient than yeast at producing alcohol and are being explored in the search for new energy sources. Escherichia coli, a normal inhabitant of the human intestinal tract, is the most thoroughly studied of all organisms. Studies of the mechanisms of genetic exchange and the biology of plasmids and bacteriophages (see Bacteriophage) of E. coli have been crucial in understanding many aspects of DNA replication and the expression of genetic material. These studies have led to the ability to insert DNA from unrelated organisms into E. coli plasmids and bacteriophages and to have that DNA replicated by the bacteria, with the genetic information it contains expressed by the bacteria. It is thus possible for bacteria to become living factories for scarce biological products such as human insulin, interferon, and growth hormone.
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Recessive. Because it is a loss of function mutation. Your body does not produce enough lactase, If it can make enough with the heterozygous alleles then it passes a threshold level enough to make you not lactose intollerant.  I mean this is a simplified model, usually this is due to several genes, you might want to look at something called genetic complemenation. \nBTW... the guy on the top is a moron. The Lactase is not dependant on the E. Coli, otherwise this wouldn't be a heritable trait.
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You have to identify two sequences that are >6kb apart from one another that flank the sequence you are attempting to amplify. Better yet, you can get you a well understood cloning vector (plasmid) that already has primers develped for it that flank the polyrestriction site region (ie. puc19 [see link below], find the needed restriction enzyme sites that flank your desired 6kb sequence and clone the DNA into the vector. Be sure to check your sequence for any internal restriction sites. This may require you to do a partial digestion and recovery.
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1.  DNA ligase ligates the DNA to a solid plasmid\n\n2. Antiboitic resistance allows you to screen bacteria that contain the new plasmid.  Any bacteria without the antibotic resistance gene will die when plated out on a plate containing the proper antibiotic.  Without antibiotic on the plate, you would have a plate with a lawn of bacteria.\n\n3  Two reasons.  Blunt ends are difficult to ligate and that lowers the cloning efficiency.  Also if it does get ligated and some portion will,  a second round of analysis will be needed to determine the orientation of the gene. Which goes to the second point\n\nIf you use two restriction enzymes with different sticky ends you can clone the insulin gene in to the vector in a directional fashion.  ie. Its not cloned in bacwards.\n\nhope this helps\n\nStooleo
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http://www.microbesonline.org/operons/gnc205922.html
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Can you explain your Q more?\nbut I can say genetic regultaion is very important in biotech\nfrom the simplest task like protein expression \n( we need to control the expression by gene regulation such as using lac operon so that the protein which may be toxic or unnatural to the host can be expressed in desirable time)\nto very advance task gene regulation is heavily involved
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polymers of L and D of galactose!and from a red alge
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An integrated microprocessor-based fermenter controller was developed in 1980 for an operational environment at Cetus Corp. The main goals in the design and construction of the system were (1) to facilitate scale-up; (2) to provide flexibility and high performance for optimizing fermentation processes; and (3) to be cost-effective for 15 in-house systems. It was also developed to work in conjunction with a laboratory minicomputer for on-line optimization experiments. The controller controls temperature, agitation, dissolved oxygen, pH, and foam throughout each fermentation run without manual intervention. The feedback control parameters have been optimized to provide very accurate control over a wide range of setpoint conditions and under rapidly changing metabolic conditions such as induced during an Escherichia coli batch run. The controller has also been configured to monitor, display, and record each of the controlled variables; support the interactive operator console; and communicate with the laboratory computer. In over 4 years of operation, these systems have met the design goals and have proven to be very reliable. The controller is described, its operational performance presented, and a typical fermentation run delineated
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You need a DNA plasmid with a few things.  First a origin of replication, so the plasmid can be replicated.  Second, an antibiotic resistance marker to issolate only bacteria containing the plasmid.  Third you need a bacterial promoter with a consensus kozak sequence followed by your gene of interest in frame.  Usually this gene is followed by or preceded by glutathione-S-transferase (GST) to facilitate purification of the protein).  Also usually the promoter contains a repressor region LacI, which means the gene is turned off normally, unless you add lactose or IPTG (a synthetic lactose), which turns on gene transcription and translation.  This is routinely done in labs nowadays.
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The operon area is essentially the regulatory center of a gene.  The operon may have several regualtory regions in which a multitude of regulator proteins may bind.  The promoter region of the operon generally regulates the transcription of the gene.
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Lactose converting into lactic acid.
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I just read an article about this. There are actually several different resitances that enterococcus becomes resistant to vancomycin. Protein's are shared between bacteria frequently, some of the proteins cause resistance to vancomycin. \n\n####\n\nVancomycin-resistant enterococci (VRE) were first reported in 1986, nearly 30 years after vancomycin was clinically introduced. The primary inciting factor was likely the use of orally administered vancomycin for treating antibiotic-associated diarrhea in hospitals. Vancomycin resistance is conferred by one of two functionally similar operons, VanA or VanB (Figure) (24). The VanA and VanB operons are highly sophisticated resistance determinants, which suggests that they evolved in other species and were acquired by enterococci. The difference in the guanine-cytosine (G-C) content of the genes of the VanB operon (roughly 50% G-C) (25) in comparison to typical enterococcal genes (35% to 40% G-C) (3) is compelling evidence for this acquisition. The conditions that would favor substantial colonization by naturally glycopeptide-resistant species (probably streptomycetes) and persistence of enterococci include high vancomycin concentrations in the gastrointestinal tract. Substantially high levels of glycopeptides in the gastrointestinal tract are achievable by oral administration, since these agents are not absorbed, resulting in fecal vancomycin concentrations high enough to favor colonization with vancomycin-resistant streptomycetes, but not high enough to kill the notably tolerant enterococcus. Hence, it is reasonable to presume that oral administration of glycopeptides to humans was a major factor in the emergence of vancomycin resistance in enterococci. The European VRE outbreak's apparent origin in animals (who were fed oral glycopeptides as growth promoters) further supports this scenario