2,3 The positive interaction between gemcitabine and radiotherapy is likely due to a combination of mechanisms that include deoxyadenosine
triphosphate depletion, cell cycle redistribution and inhibition of DNA synthases and repair.
MDA reacts with deoxyadenosine
and deoxyguanosine in DNA, forming DNA MDA and other thiobarbituric acid reactive substances (TBARS) condense with two equivalents of thiobarbituric acid to give a fluorescent red derivative.
TK is a key enzyme in the pyrimidine salvage pathway, catalyzing the transfer of the terminal phosphate from adenosine triphosphate to the 5'-hydroxyl group of thymidine, producing deoxyadenosine
triphosphate, which is subsequently incorporated into DNA.
This enzyme irreversibly converts adenosine to inosine and deoxyadenosine
to deoxyinosine, and the speed rate of this reaction gives an account of enzymatic activity, calculated as ADA concentration in the laboratory.
E-ADA is considered to be a key enzyme in the purine metabolism, catalyzing the irreversible deamination of adenosine and deoxyadenosine
to inosine and deoxyinosine, respectively, and closely regulating extracellular adenosine and inosine concentrations (9,10).
In pyrosequencing, the natural deoxyadenosine
triphosphate (dATP) results in false signals because, like ribose adenosine 5'-triphosphate (rATP), it is a substrate for luciferase.
TA cloning is achieved by Taq DNA polymerase which has non-template-dependent terminal transferase activity which helps adding of a single deoxyadenosine
(A) to the 3' ends of PCR products.
Adenosine deaminase (ADA), an enzyme of purine salvage and catabolic pathway deaminates adenosine and deoxyadenosine
to form inosine and deoxy inosine respectively.
ADA has a role in purine metabolism that converts adenosine and deoxyadenosine
to inosine and deoxyinosine by irreversible deamination (20).
ABBREVIATIONS: bDNA = Branched DNA; DNA = Deoxyribonucleic Acid; dNTP = Deoxyribonucleotides; dATP = Deoxyadenosine
Triphosphate; dCTP = Deoxycytidine Triphosphate; dGTP = Deoxyguanosine Triphosphate; dTTP = Deoxythymidine Triphosphate; FDA = Food and Drug Administration; FRET = Fluorescence Resonance Energy Transfer; MRSA = Methicillin Resistant Staph aureus; MTB = Mycobacterium tuberculosis; NASBA = Nucleic Acid Sequence Based Amplification; PCR = Polymerase Chain Reaction; PFGE = Pulsed-Field Gel Electrophoresis; RT-PCR = Reverse Transcription Polymerase Chain Reaction; Taq = Thermus aquaticus; TMA = Transcription-Mediated Amplification; VRE = Vancomycin Resistant Enterococcus.
Adenosine deaminase (ADA) is an enzyme in the purine salvage pathway that catalyses the conversion of adenosine and deoxyadenosine
to inosine and deoxyinosine with the release of ammonia.
The commonly used cloning strategy utilizes the feature of Taq DNA polymerase to add a 3' overhanging deoxyadenosine
residues in most of the PCR products (1).