Topic
Coenzyme analog
About: Coenzyme analog is a research topic. Over the lifetime, 64 publications have been published within this topic receiving 1392 citations.
Papers published on a yearly basis
Papers
TL;DR: The spectroscopic results with nicotinamide 1,N(6)-ethenoadenine din nucleotide are consistent with the concept of an intramolecular interaction between the modified adenine and pyridine moieties of the dinucleotide that is disrupted by enzymatic hydrolysis.
Abstract: Nicotinamide 1,N6-ethenoadenine dinucleotide, a fluorescent analog of the coenzyme nicotinamide adenine dinucleotide, has been synthesized by the reaction of chloroacetaldehyde with the coenzyme. The technical fluorescence emission maximum of the analog is 410 nm, upon excitation at 300 nm. Its fluorescence yield is about 8% of that of the 1,N6-ethenoadenine 5′-phosphate, and its fluorescence lifteime is shorter. Upon hydrolysis of the modified coenzyme analog with Neurospora crassa NADase or phosphodiesterase I at room temperature, the intensity of fluorescence was increased 10-fold, corresponding to separation of the nicotinamide and ethenoadenine rings. The spectroscopic results with nicotinamide 1,N6-ethenoadenine dinucleotide are consistent with the concept of an intramolecular interaction between the modified adenine and pyridine moieties of the dinucleotide that is disrupted by enzymatic hydrolysis. The fluorescent analog showed reasonable activity as a substitute for NAD+ in four different dehydrogenase-catalyzed reactions.
116 citations
TL;DR: Different classes of folate analogues have been examined with respect to the mechanism of their inhibition of dihydrofolate reductases from Escherichia coli and chicken liver and the degree of synergism between the binding of these compounds and NADPH has been investigated.
92 citations
TL;DR: The unique ability of ubiquinones to both bind and provide the appropriate redox span is discussed and strong entropy-enthalpy compensation is suggested to arise from antagonistic interactions (anticooperativity) between headgroup and tail binding.
90 citations
TL;DR: This chapter discusses the preparation of the reduced forms of vitamin B 12, and the reaction between secondary halides such as α-chloropropionic acid and 2-bromobutane is fast, but the resulting coenzyme analogs are not sufficiently stable to survive the purification procedures.
Abstract: Publisher Summary This chapter discusses the preparation of the reduced forms of vitamin B 12 . B 12s is the most nucleophilic species known to exist in aqueous solution, and this high nucleophilicity results in the ease of preparation of the B 12 coenzyme and its analogs, because B 12s undergoes both rapid substitution and addition reactions with a variety of electrophiles. The chapter also discusses the preparation of alkyl and acyl analogs of the vitamin B 12 cocnzyme general considerations. The preparation of such analogs is based upon the reaction of B 12s with suitable electrophiles. The limiting factors in the synthesis of B 12 coenzyme analogs by nucleophilic displacement reactions are primarily steric, and they may either limit the rate of the reaction or affect the stability of the coenzyme analog once it has been formed. Thus, no reaction is observed between B 12s and neopentyl chloride, while the reaction between secondary halides such as α-chloropropionic acid and 2-bromobutane is fast, but the resulting coenzyme analogs are not sufficiently stable to survive the purification procedures.
74 citations
TL;DR: It is concluded that zinc ion has a Lewis acid function in facilitating the chemical activation of the aldehyde carbonyl for reduction, and that reduced coenzyme plays a noncovalent effector role in this substrate activating step.
Abstract: 1,4,5,6-Tetrahydronicotinamide adenine dinucleotide (H2NADH) has been investigated as a reduced coenzyme analog in the reaction between trans-4-N,N-dimethylaminocinnamaldehyde (I) (lambdamax 398 nm, epsilonmax 3.15 X 10-4 M-minus 1 cm-minus 1) and the horse liver alcohol dehydrogenase-NADH complex. These equilibrium binding and temperature-jump kinetic studies establish the following. (i) Substitution of H2NADH for NADH limits reaction to the reversible formation of a new chromophoric species, lambdamax 468 nm, epsilonmax 5.8 x 10-4 M-minus 1 cm-minus 1. This chromophore is demonstrated to be structurally analogous to the transient intermediate formed during the reaction of I with the enzyme-NADH complex [Dunn, M. F., and Hutchison, J. S. (1973), Biochemistry 12, 4882]. (ii) The process of intermediate formation with the enzyme-NADH complex is independent of pH over the range 6.13-10.54. Although studies were limited to the pH range 5.98-8.72, a similar pH independence appears to hold for the H2NADH system. (iii) Within the ternary complex, I is bound within van der Waal's contact distance of the coenzyme nicotinamide ring. (iv) Formation of the transient intermediate does not involve covalent modification of coenzyme. Based on these findings, we conclude that zinc ion has a Lewis acid function in facilitating the chemical activation of the aldehyde carbonyl for reduction, and that reduced coenzyme plays a noncovalent effector role in this substrate activating step.
64 citations
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Performance Metrics
| Year | Papers |
|---|---|
| 2019 | 1 |
| 2018 | 1 |
| 2013 | 1 |
| 2011 | 1 |
| 2008 | 1 |
| 2006 | 1 |