active site

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Related to active sites: Lock and Key Model, induced fit model

ac·tive site

that portion of an enzyme molecule at which the actual reaction proceeds; considered to consist of one or more residues or atoms in a spatial arrangement that permits interaction with the substrate to effect its reaction.

active site

The part of an enzyme at which catalysis of the substrate occurs.

active site

the place on the surface of an enzyme where its catalytic action occurs.

Active Site

The site in an enzyme where a substrate binds and an enzymatic reaction—e.g., ligation, oxidoreduction, etc.—occurs. The structure of the amino acid residues within the active site enhances substrate binding, substrate activation, and formation of a transition state.

ac·tive site

(ak'tiv sīt)
That portion of an enzyme molecule at which the actual reaction proceeds; one or more residues or atoms in a spatial arrangement that permits interaction with the substrate.

active site

1. The region of an ENZYME to which the substance being affected binds so as to undergo a catalyzed reaction.
2. The localized part of a protein to which a substrate binds.
Active siteclick for a larger image
Fig. 11 Active site . Lock-and-key mechanism of enzyme activity.

active site

an area of ENZYME surface which has a shape complementary to a particular SUBSTRATE, enabling the enzyme and substrate to become temporarily bonded to form an enzyme-substrate complex. Such a lock-and-key mechanism explains the great specificity of enzymes for substrates and also why changes in enzyme three-dimensional shape (by pH, temperature) cause alterations to enzyme activity.


not passive.

active principle
the drugs or chemicals in a pharmaceutical preparation that exert an effect pharmacologically; as distinct from the inert fillers, wetting agents and other excipients also often included.
active site
that region of a protein, usually an enzyme, that binds to another molecule such as the substrate of the enzyme.
active transport
the movement of ions or molecules assisted by a carrier protein across the cell membranes and epithelial layers, usually against a concentration gradient, resulting directly from the expenditure of metabolic energy. For example, under normal circumstances more potassium ions are present within the cell and more sodium ions extracellularly. The process of maintaining these normal differences in electrolytic composition between the intracellular fluids is active transport. The process differs from simple diffusion or osmosis in that it requires the expenditure of metabolic energy.

Patient discussion about active site

Q. Are there any nice activities for adults with autism? I've been helping a very nice man of 45 of years old and I'm looking for some new things I can do with him in our time together. any ideas?

A. Autistic people react wonderfully with animals. for instance- i saw a group of severe Autistic teenagers going to swim with dolphins. the effect was amazing! taking him to the zoo, or even to the park to feed ducks, pet dogs, whatever.. could have a great effect on him.
hope i helped!
tell me how it went.

Q. what is a passive smoking? and is it dangerous as an active?

A. Passive smoking is the exposure to cigarettes smoke emitted from cigarettes smoke by other person. It's dangerous and may increase the risk to several diseases similar to active smoking (one's exposure to smoke emitted from the cigarettes he or she is smoking) although the risk is of lower magnitude. Example for passive smoking is children of smokers etc.

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Q. i swim a lot ! what are the advantages of swimming over other sport activities? on what part of the body does it work the most ?

A. its a good workout but your not really going to burn as much calories as a regular work out.

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References in periodicals archive ?
We created a simple and effective bioinformatics module to test its efficacy in educating students about phylogeny as well as visualizing and locating the active site of the subject enzymes in an undergraduate one-semester biochemistry class.
Then the active site and various conserved motifs of the enzyme were determined by sequence alignment with the lysosomal lipase of Homo sapiens (Accession # CAA83495.
Much attention has been dedicated to polydispersities because of the likely existence of multiple active sites and of the difficulty to reproduce the catalyst synthesis.
The complexity of the active site explains the problems of reproducibility.
5 A resolution was confirmed, whereas the two active site histidines had to be rotated around CBCG bonds in order to agree with the difference maps.
All of the other active sites are located in an industrial area south of Mojave along United Street.
He continued: "We have active sites across the region and have recently started work on six new developments.
The group, which also trades as David Wilson and Ward Homes, intends to increase completions in the current year with the number of active sites due to rise to 400 from 354.
In the period of the trading update, Barratt said it operated from an average of 349 active sites.
For split, splitless, or large volume injections, the Titan XL is a single injection system that incorporates the latest improvements in coil/cartridge heating, flexible cooling options, baffled liner technology, and an Inertium coating, which is extremely inert and reduces breakdown caused by active sites in the inlet.
Under the terms of the agreement, GeneFormatics will utilize its proteomics technologies to identify all members of the M10 family of matrix metalloproteinases in the human proteome and characterize the structure and chemistry of active sites.
pylori urease has more active sites than other ureases--and can pump out more ammonia per enzyme.

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