TY - JOUR
T1 - Immunochemical determination of the molecular conformation of nucleotides
AU - Estrada-Parra, Sergio
AU - García-Ortigoza, Ethel
N1 - Funding Information:
It is well known that antibodies can differentiate between compounds of similar structure such as ortho, para or meta benzoic acids (Landsteiner, 1945) or between alpha D-glucopyranose and beta o-glucopyranose among others (Avery et al., 1932). This fine discriminating capacity of antibodies could be used to study molecular conformation of nucleotides. In a previous publication (Estrada-Parra and Garcia-Ortigoza, 1968) we presented preliminary data showing that antibodies against adenylic acid (AMP) could be used to study the molecular conformation of compounds such as adenosine triphosphate (ATP), nicotinamide adenine dinudeotide (NAD), nicotinamide adenine dinucleotide phosphate (NADP), adenosine diphosphate (ADP) and others, all of which have an adenine base in common. We expected that,anti-AMP antibodies could react with all these molecules as well as it reacts~,with AMP Since this was not the case it was suggested that in these mOlecules :the adenine was not available for reaction with anti-AMP antibodies, On the other hand it has been proposed by Szent-Gy6rgyi (1957) that in the ATP molecule the phosphate groups can be *Supported in part by a grant from the Brown Hazen Fund of the Research Corporation. tFellow of the C.O.F.A.A. of the I.P.N.
PY - 1972/8
Y1 - 1972/8
N2 - Rabbit gamma globulin anti-adenosine monophosphate-egg albumin (AMP-EA) was used to study the molecular conformation of nucleotides such as adenosine triphosphate (ATP) or adenosine diphosphate (ADP). The study was done uisng AMP, ADP, and ATP, under different conditions, to inhibit the precipitin reaction between AMP-human serum albumin (HSA) and anti-AMP-EA. When the haptens were dissolved in 0·15M saline at pH 7·0, the best inhibitor was AMP followed by ADP and then by ATP. If the haptens were dissolved in 0.02M disodium ethylene diamino tetra-acetate (EDTA)-0.15·M saline at pH 7·0, the inhibition by AMP was not modified but both ADP and ATP inhibited as well as AMP. Finally if the haptens were dissolved in 0·02M MgCl2-0·15M saline at pH 7·0, again AMP inhibited as before but ADP and ATP inhibited less than wehn dissolved in saline alone. ATP in saline or with magnesium ions (Mg++) inhibited less than ADP in the same conditions. These results indicate that ADP and ATP have a folded molecular conformation with Mg++ participating in it in such a way that antibodies specific for the adenine base cannot react with them as well as with AMP which does not have this folded configuration. EDTA removes the Mg++, causing an unfolding of the ATP or ADP molecule and facilitating in this way their reaction with anti-AMP antibodies in the same manner as with AMP alone.
AB - Rabbit gamma globulin anti-adenosine monophosphate-egg albumin (AMP-EA) was used to study the molecular conformation of nucleotides such as adenosine triphosphate (ATP) or adenosine diphosphate (ADP). The study was done uisng AMP, ADP, and ATP, under different conditions, to inhibit the precipitin reaction between AMP-human serum albumin (HSA) and anti-AMP-EA. When the haptens were dissolved in 0·15M saline at pH 7·0, the best inhibitor was AMP followed by ADP and then by ATP. If the haptens were dissolved in 0.02M disodium ethylene diamino tetra-acetate (EDTA)-0.15·M saline at pH 7·0, the inhibition by AMP was not modified but both ADP and ATP inhibited as well as AMP. Finally if the haptens were dissolved in 0·02M MgCl2-0·15M saline at pH 7·0, again AMP inhibited as before but ADP and ATP inhibited less than wehn dissolved in saline alone. ATP in saline or with magnesium ions (Mg++) inhibited less than ADP in the same conditions. These results indicate that ADP and ATP have a folded molecular conformation with Mg++ participating in it in such a way that antibodies specific for the adenine base cannot react with them as well as with AMP which does not have this folded configuration. EDTA removes the Mg++, causing an unfolding of the ATP or ADP molecule and facilitating in this way their reaction with anti-AMP antibodies in the same manner as with AMP alone.
UR - http://www.scopus.com/inward/record.url?scp=0015387209&partnerID=8YFLogxK
U2 - 10.1016/0019-2791(72)90259-5
DO - 10.1016/0019-2791(72)90259-5
M3 - Artículo
SN - 0019-2791
VL - 9
SP - 799
EP - 807
JO - Immunochemistry
JF - Immunochemistry
IS - 8
ER -