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

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

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.

You may read more here:http://www.nlm.nih.gov/medlineplus/secondhandsmoke.html

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 ?
1B illustrates the prepared structures of the protein after removal of hetero atoms, ligands and water molecules with a sphere around the active site.
Active Site. In the structure of the apo form, putative isocitrate-binding residues (Ser109, Asn111, Arg115, Arg125, Arg149, Asp298, Tyr156, Lys223', Asn225', and Arg274', the prime designates a residue from the adjacent subunit) involved in the binding of isocitrate in prokaryotic NADPIDHs are exposed to the inner surface in the deep cleft of the active site (Figure 3).
The [zeta] CA active site resembles that of [beta] Cas coordinating the metal ion to a His and two Cys residues (x, x+52, x+62, where x=263 in CDCA1) [45].
In the 1990s, homology models of CYP1A1 and CYP1A2 binding sites were generated from the bacterial CYP102 crystal structure via residue replacement and energy minimization procedures, and a series of known substrates and inhibitors of the CYP1A subfamily were docked interactively to the active sites [22].
The major interactions between 5 and PTP1B active sites are shown in Figure 8(b), which was similar to 3.
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.
For the 3-phytase A, the active site is conformed by amino acids [R.sub.58], [H.sub.59], [R.sub.62], [R.sub.142], and [D.sub.339] [22] (Figure 3(b)), and for the 3-phytase B the active site is conformed by amino acids [R.sub.62], [H.sub.63], [R.sub.66], [R.sub.156], [H.sub.318], and [D.sub.319] [21] (Figures 3(c) and 3(d)).
LeadIT (FlexX) is a flexible docking method that uses an incremental construction (IC) algorithm and a pure empirical scoring function similar to the one developed by Bohm and coworkers to place ligands into the active site. IC algorithms first dissect each molecule into a set of rigid fragments according to rotatable bonds and then incrementally assemble the fragments around the binding pocket.
The NarL protein (in the asymmetric unit) is a homotetramer containing 4 identical subunits having their independent active sites each for subunits A, B, C, and D, respectively.
Serine-carboxyl peptidases are a kind of pepstatin-insensitive acid peptidases and are classified in the MEROPS peptidase data as family S53 enzymes including sedolisin and its homologs, which possess catalytic serine and carboxyl groups at the active sites. They are structurally related to subtilisin.
A lot of research has been developed on the performance improvement of semiconductor material by providing active sites and structuring semiconductor surface [2-7].
Based on technology to remove heavy metals from waste streams, the highly porous silica substrate maximizes the density of chemically active sites, allowing facile diffusion through the domains of the sorbent material.

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