|
Search over 100 encyclopedias and dictionaries: |
Research categories | Follow us on Twitter |
Research categories
View all topics in the newsView all reference sources at Encyclopedia.com |
|||
NAD
NAD (nicotinamide adenine dinucleotide) A coenzyme, derived from the B vitamin nicotinic acid, that participates in many biological dehydrogenation reactions (see formula). NAD is characteristically loosely bound to the enzymes concerned. It normally carries a positive charge and can accept one hydrogen atom and two electrons to become the reduced form, NADH. NADH is generated during the oxidation of food, especially by the reactions of the Krebs cycle. It then gives up its two electrons (and single proton) to the electron transport chain, thereby reverting to NAD+ and generating three molecules of ATP per molecule of NADH.
NADP (nicotinamide adenine dinucleotide phosphate) differs from NAD only in possessing an additional phosphate group. It functions in the same way as NAD although anabolic reactions (see anabolism) generally use NADPH (reduced NADP) as a hydrogen donor rather than NADH. Enzymes tend to be specific for either NAD or NADP as coenzyme. |
|
|
Cite this article
"NAD." A Dictionary of Biology. 2004. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "NAD." A Dictionary of Biology. 2004. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O6-NAD.html "NAD." A Dictionary of Biology. 2004. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-NAD.html |
|
NAD
NAD n. nicotinamide adenine dinucleotide: a coenzyme that acts as a hydrogen acceptor in oxidation-reduction reactions, particularly in the electron transport chain in cellular respiration. NAD and the closely related coenzyme NADP (nicotinamide adenine dinucleotide phosphate) are derived from nicotinic acid; they are reduced to NADH and NADPH, respectively.
|
|
|
Cite this article
"NAD." A Dictionary of Nursing. 2008. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "NAD." A Dictionary of Nursing. 2008. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O62-NAD.html "NAD." A Dictionary of Nursing. 2008. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-NAD.html |
|
NAD
NAD, NADP Nicotinamide adenine dinucleotide and its phosphate, the coenzymes derived from niacin. Involved as hydrogen acceptors in a wide variety of oxidation and reduction reactions.
|
|
|
Cite this article
DAVID A. BENDER. "NAD." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. DAVID A. BENDER. "NAD." A Dictionary of Food and Nutrition. 2005. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O39-NADNADP.html DAVID A. BENDER. "NAD." A Dictionary of Food and Nutrition. 2005. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O39-NADNADP.html |
|
Nad
Nad (Nead an Iolair) Cork. ‘Eagle's nest’.
|
|
|
Cite this article
A. D. MILLS. "Nad." A Dictionary of British Place-Names. 2003. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. A. D. MILLS. "Nad." A Dictionary of British Place-Names. 2003. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O40-Nad.html A. D. MILLS. "Nad." A Dictionary of British Place-Names. 2003. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O40-Nad.html |
|
NAD
NAD See NICOTINAMIDE ADENINE DINUCLEOTIDE.
|
|
|
Cite this article
MICHAEL ALLABY. "NAD." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "NAD." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O7-NAD.html MICHAEL ALLABY. "NAD." A Dictionary of Plant Sciences. 1998. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-NAD.html |
|
NAD
NAD See NICOTINAMIDE ADENINE DINUCLEOTIDE.
|
|
|
Cite this article
MICHAEL ALLABY. "NAD." A Dictionary of Zoology. 1999. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "NAD." A Dictionary of Zoology. 1999. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O8-NAD.html MICHAEL ALLABY. "NAD." A Dictionary of Zoology. 1999. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O8-NAD.html |
|
NAD
NAD see coenzyme . |
|
|
Cite this article
"NAD." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. "NAD." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1E1-X-NAD.html "NAD." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-NAD.html |
|
NAD
NAD (USA) National Academy of Design
• Biochem. nicotinamide adenine dinucleotide • Med. no abnormality detected • (or n.a.d.) no appreciable difference • not on active duty |
|
|
Cite this article
FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "NAD." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. 26 May. 2012 <http://www.encyclopedia.com>. FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "NAD." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. (May 26, 2012). http://www.encyclopedia.com/doc/1O25-NAD.html FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "NAD." The Oxford Dictionary of Abbreviations. 1998. Retrieved May 26, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O25-NAD.html |
|