000			04425nam a22005175i 4500
001			978-0-387-72891-9
003			DE-He213
005			20161121230751.0
007			cr nn 008mamaa
008			100301s2008 xxu| s |||| 0|eng d
020			_a9780387728919 _9978-0-387-72891-9
024	7		_a10.1007/978-0-387-72891-9 _2doi
050		4	_aQD431-431.7
072		7	_aPSBZ _2bicssc
072		7	_aSCI007000 _2bisacsh
082	0	4	_a572.6 _223
100	1		_aTraut, Thomas. _eauthor.
245	1	0	_aAllosteric Regulatory Enzymes _h[electronic resource] / _cby Thomas Traut.
264		1	_aBoston, MA : _bSpringer US, _c2008.
300			_aXIV, 250 p. _bonline resource.
336			_atext _btxt _2rdacontent
337			_acomputer _bc _2rdamedia
338			_aonline resource _bcr _2rdacarrier
347			_atext file _bPDF _2rda
505	0		_aOverview Of Enzymes -- To Enzymes -- The Limits For Life Define The Limits For Enzymes -- Enzyme Kinetics -- Properties And Evolution Of Allosteric Enzymes -- Kinetics Of Allosteric Enzymes -- K-Type Enzymes -- Hemoglobin -- Glycogen Phosphorylase -- Phosphofructokinase -- Ribonucleotide Reductase -- Hexokinase -- V-Type Enzymes -- To V-Type Enzymes -- G Proteins -- Protein Kinases.
520			_aAll enzymes are remarkable since they have the ability to increase the rate of a chemical reaction, often by more than a billion-fold. Allosteric enzymes are even more amazing because the have the additional ability to change their rate in response to cellular activators or inhibitors. This enables them to control the pathway in which they are the regulatory enzyme. Since the effector molecules represent the current status of the cell for a given metabolic pathway, this results in very responsive and balanced metabolic states, and makes it possible for cells and organisms to be appropriately dynamic, and responsive, in a changing environment. This book provides a logical introduction to the limits for enzyme function as dictated by the factors that are limits for life. This book presents a complete description of all the mechanisms used for changing enzyme acticity. Eight enzymes are used as model systems after extensive study of their mechanisms. Wherever possible, the human form of the enzyme is used to illustrate the regulatory features. While authors often emphasize the few enzymes that have the most remarkable catalytic rates, this survery of enzymes has led to the author's appreciation of some important, general conclusions: 1. Most enzymes are not exceptionally fast; they are always good enough for their specific catalytic step. 2. Although enzymes could always be much faster if they changed so as to bind their substrates more weakly, actual enzymes must be able to discriminate in favor of their special substrate, and therefore they have sacrificed speed to obtain better binding. This means that specific control of individual metabolic steps is more important than overall speed. 3. Results for many hundreds of enzymes establish that a lower limit for a normal catalytic activity is 1 s-1. Most enzymes have a catalytic rate between 10 and 300 s-1. 4. Allosteric regulation always results in a chance in the enzymes's affinity for its substrate. Even V-type enzymes (named for their large chance in catalytic velocity) always have a corresponding change in affinity for their substrate. Thomas Traut has a PhD in molecular biology and has studied enzymes since 1974. As a professor at the University of North Carolina at Chapel Hill, he has focused on enzyme regulation and taught advanced enzymology to graduate students. Important findings from his research helped to define the mechanism of allosteric control for dissociating enzymes. .
650		0	_aLife sciences.
650		0	_aChemistry.
650		0	_aBiochemistry.
650		0	_aEnzymology.
650		0	_aCell biology.
650		0	_aBiomedical engineering.
650	1	4	_aLife Sciences.
650	2	4	_aEnzymology.
650	2	4	_aBiochemistry, general.
650	2	4	_aBiomedical Engineering.
650	2	4	_aCell Biology.
650	2	4	_aChemistry/Food Science, general.
650	2	4	_aBiomedicine general.
710	2		_aSpringerLink (Online service)
773	0		_tSpringer eBooks
776	0	8	_iPrinted edition: _z9780387728889
856	4	0	_uhttp://dx.doi.org/10.1007/978-0-387-72891-9
912			_aZDB-2-SBL
950			_aBiomedical and Life Sciences (Springer-11642)
999			_c503667 _d503667