Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Several reverse transcriptases were studied for their ability to accept anhydrohexitol triphosphates, having a conformationally restricted six-membered ring, as substrate for template-directed synthesis of HNA. It was found that AMV, M-MLV, M-MLV (H(-)), RAV2 and HIV-1 reverse transcriptases were able to recognise the anhydrohexitol triphosphate as substrate and to efficiently catalyse the incorporation of one non-natural anhydrohexitol nucleotide opposite a natural complementary nucleotide. However, only the dimeric enzymes, the RAV2 and HIV-1 reverse transcriptases, seemed to be able to further extend the primer with another anhydrohexitol building block. Subsequently, several HIV-1 mutants (4xAZT, 4xAZT/L100I, L74V, M184V and K65A) were likewise analysed, resulting in selection of K65A and, in particular, M184V as the most succesful mutant HIV-1 reverse transcriptases capable of elongating a DNA primer with several 1,5-anhydrohexitol adenines in an efficient way. Results of kinetic experiments in the presence of this enzyme revealed that incorporation of one anhydrohexitol nucleotide of adenine or thymine gave an increased (for 1,5-anhydrohexitol-ATP) and a slightly decreased (for 1,5-anhydrohexitol-TTP) K(m) value in comparison to that of their natural counterparts. However, no more than four analogues could be inserted under the experimental conditions required for selective incorporation. Investigation of incorporation of the altritol anhydrohexitol nucleotide of adenine in the presence of M184V and Vent (exo(-)) DNA polymerase proved that an adjacent hydroxyl group on C3 of 1,5-anhydrohexitol-ATP has a detrimental effect on the substrate activity of the six-ring analogue. These results could be rationalised based on the X-ray structure of HIV-1 reverse transcriptase.
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PMID:Reverse transcriptase incorporation of 1,5-anhydrohexitol nucleotides. 1147 Aug 72

DNA microarrays and sensors have become essential tools in the functional analysis of sequence information. Recently we reported that chimeric hexitol (HNA) and altritol (ANA) nucleotide monomers with an anhydrohexitol sugar moiety are easily available and proved their chemistry to be compatible with DNA and RNA synthesis. In this communication we describe a novel analytical platform based on HNA and ANA units to be used as synthetic oligonucleotide arrays on a glass solid support for match/mismatch detection of DNA and RNA targets. Arrays were fabricated by immobilization of diene-modified oligonucleotides on maleimido-activated glass slides. To demonstrate the selectivity and sensitivity of the HNA/ANA arrays and to compare their properties with regular DNA arrays, sequences in the reverse transcriptase gene (codon 74) and the protease gene of HIV-1 (codon 10) were selected. Both, the relative intensity of the signal and match/mismatch discrimination increased up to fivefold for DNA targets and up to 3-3.5-fold for RNA targets applying HNA or ANA arrays (ANA>HNA>DNA). Certainly in the new field of miRNA detection, ANA arrays could prove very beneficial and their properties should be investigated in more detail.
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PMID:HNA and ANA high-affinity arrays for detections of DNA and RNA single-base mismatches. 1837 34