14 May 2011

PROTEIN ENGINEERING


The protein engineering is an valuable tool to yield superior enzymes and storage space proteins. To sort out this, a protein engineer is vital to arrange a notebook aided protein develop pro a point function and at that time arrange a phony gene with the intention of will yield this desired protein in a pre-decided and predictable style. Using the practice of ‘site directed mutagenesis’, changes are made in genes by renowned sites leading to the modification of function in a preset style. The ‘computational and graphical tools’ allow the spectacle and exploration of three dimensional structures of proteins. These two techniques are very helpful in deciding in this area the three dimensional organize of protein/drug looked-for pro a point function previous to using recombinant genetic material equipment pro proteins or organic synthesis pro drugs.

Protein Engineering involves the following steps:

A)         Preparation of a protein sample from an organism.

B)         Characterization of the sample with a ligand such as enzyme-substrate, receptor-hormone or antigen-antibody interaction.

C)         Analysis of the three dimensional (3-D) organize through NMR (nuclear magnetic resonance) and X-ray diffraction pattern of crystals.

D)         Displaying of the 3-D organize with interactive notebook graphics.

E)         Processing of the in rank to excellent a novel design apposite to the vital needs.

F)         The desired genetic material sequence which is probable to produce the novel designed protein is at that time either synthesized or obtained by locate directed mutagenesis of an unfilled gene.

G)         Introduction of the novel gene into a apposite face logic followed by it’s refining and biochemical characterization.

H)         If biochemical characterization does not fit the earlier predicted organize, the cycle is continual again.

Uses of protein engineering

The protein engineering is being used
A) to create superior enzymes with the room to catalyze the production of distinguished regard point chemicals;
B) in the production of enzymes pro generous extent aid in the compound industry;
C) in the production of biological compounds counting phony peptides, storage space proteins and point drugs with the intention of are superior to the natural ones.

There is an impressive catalog of proteins with the intention of be inflicted with been altered using protein engineering equipment. Inside ‘T4 Lysozyme’, a change of isoleucine to cystine leads to the formation of a disulphide join which gave thermal stability and a 200 fold boost in enzyme endeavor by a warmth of 670c. The confiscation of lone of the three cysteine residues in the creature beta interferon led to an enhancement in stability of the enzyme. The enzyme ‘Trypsin’ may possibly be redesigned to be inflicted with altered substrate specificity. The substrate specificity of lactic protease (in E. Coli.) has been publicized to be dramatically modified by replacing committed locate methionine by alanine.

Protein engineering is furthermore being used to create immunotoxins, which are the conjugates of cell binding antibody or antigens, covalently bound to a sow or a bacterial toxin. The procedure of fusion of genes using sequences coding pro antibodies and toxic peptides is used to create these immunotoxins. When a uncomplaining is treated with the immunotoxins, the antibody or antigen helps in the recognition of the target cells to be killed and the toxin element helps in butchery these cells. So immunotoxins are produced in such a way with the intention of they be inflicted with two parts- a) a toxin polypeptide or a part of it having toxin endeavor, called A string, and b) a cell binding recognition polypeptide or antibody or a part of it having binding locate, called B string. E.G. Ricin, a sow toxin has in fact been used as a immunotoxin pro a study of it’s effect on mouse tumour cells.

Drug crafty is a further imminent area in biotechnology. Depending on the mode of proceedings used by the drugs, the drug crafty can be modified by blocking the enzyme endeavor. E.G. Trimethoprim (TMP) is a clinically valuable antimicrobial drug which inhibits the enzyme dihydrofolate reductase (dHFR) in bacteria and therefore, is used to handle urinary tract infections. However in distinguished concentrations it starts attacking creature dHFR hence apt detrimental. Efforts be inflicted with been made to synthesize TMP, which will be inflicted with a rigid three dimensional organize in friendship with bacterial enzyme dHFR, so with the intention of it could not be able to attack creature dHFR.

Another model is of enzyme Renin. Inhibitors of enzyme ‘renin’ are furthermore being actively modeled. The enzyme catalyses, the initially in a run of reactions with the intention of principal to elevated blood pressure. The hard work are vacant on to design nonpeptide inhibitors with the intention of mimic the intermediate products in the result of renin with it’s substrate and so stops the functioning of renin. These inhibitors will help in treating the hypertension.

Drugs are furthermore being produced by studying the receptor molecules associated with a fastidious disease and at that time result chemicals which can check these receptors. One of the examples is the drug ‘Propranolol’ which is used to handle sensitivity diseases and hypertension. The two hormones, ‘norepinephrine’ and ‘epinephrine’ controls the contraction and repose of cardiac muscles. These hormones play a role through the two receptors alpha (œ ) and beta ( ß). The drug propranolol blocks the receptor beta (ß ) and so inhibits the endeavor of hormones which play a role through a receptor molecule. This relaxes the sensitivity muscle. This drug is being used to handle sensitivity diseases, angina pectoris and distinguished blood pressure.

Another drug, ‘Cimetidine’ is an antiulcer medicine agreed to handle ulcers. Ulcers are caused from acid production due to histamine relief in the stomach. The drug ‘Cimetidine’ blocks the histamine receptors which prevents the acid production due to thumbs down availability of histamine. This leads to the remedial of ulcers.

The detailed studies of antimetabolites or inhibitors of genetic material synthesis has led to the development of drugs pro treating ‘cancer’, ‘gout’, ‘malaria’ and approximately viral infections like Herpes. Drugs like ‘6-mercaptopurine’ and ‘thioguanine’ by inhibiting the genetic material synthesis and the cell division, are very effectual in cancer chemotherapy. Based on the same opinion of inhibition of nucleic acid synthesis, the drugs like ‘pyramethamine’ pro malaria, ‘trimethoprim’ pro bacterial infection, and ‘acyclovir’ pro herpes virus infection and that were furthermore urban.

The area of investigate in drug crafty and development of immunotoxins is receiving lots of accent as it could be the answer pro all the prospect problems associated with the diseases correlated to extra viruses and strong bacterias. It could furthermore produce a breakthrough pro treating diseases like AIDS and cancer which take up again to challenge and threaten the creature population.


Protein engineering - from the humble spider to the nanotechnology prospect of material design
(Nanowerk Spotlight) Much has been on paper in this area the fascinating properties of spider silk, a biopolymer with the intention of is stronger than steel and more supple than rubber. The silken threads possess a unique combination of mechanical properties: Strength (its tensile strength is in this area five era as strong a steel of the same density), extensibility (up to 30%) and roughness (its skill to absorb a generous amount of energy lacking breaking). Of way this begs the obvious question: How is it doable with the intention of spider silk - produced by little creatures with the intention of evolved in this area 400 million years past - can be as strong as steel - a present alloy with the intention of the stage a vital role in our infrastructure and which still attracts extensive R&D funds in its production equipment?
What is perplexing is with the intention of the atomic interactions (hydrogen- or H-bonds) in spider silk are in fact 100 to 1,000 era weaker than persons in steel, or than persons in the super-fiber Kevlar, everywhere covalent bonds are used. Hydrogen bonds are the basic compound bonds with the intention of call collectively proteins, akin to trusses and beams in buildings, and mess about a answer role in scheming the behavior of these structures. Inside order to get to silk's mechanical properties, generally phony equipment should be much denser, hence much heavier and consume much more energy all through their synthesis and convey.
Protein engineering  Nanotechnology see more-- www.nanowerk.com

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