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Gan, S. K.

Publications and source records attributed to Gan, S. K..

2 recordsLinked to original sources

Probability of Change in Life: amino acid changes in single nucleotide substitutions

Mutations underpin the processes in life, be it beneficial or detrimental. While mutations are assumed to be random in the bereft of selection pressures, the genetic code has underlying computable probabilities in amino acid phenotypic changes. With a wide range of implications including drug resistance, understanding amino acid changes is important. In this study, we calculated the probabilities of substitutions mutations in the genetic code leading to the 20 amino acids and stop codons. Our calculations reveal an enigmatic in-built self-preserving organization of the genetic code that averts disruptive changes at the physicochemical properties level. These changes include changes to start, aromatic, negative charged amino acids and stop codons. Our findings thus reveal a statistical mechanism governing the relationship between amino acids and the universal genetic code.

molecular biology

Inhibiting HIV-1 and MMLV Reverse Transcriptase: The potential of an Allosteric Broad-Spectrum Inhibitor

HIV drug resistance continues to demand for alternative drug targets. Since Reverse Transcriptase (RT) is unique and critical for the virus life cycle, it is a rational target that is likely to have less off-target effects in humans. Serendipitously, we found two chemical compound scaffolds from the NCI Diversity Set V that inhibited the HIV1- RT catalytic activity. Computational structural analyses and subsequent experimental testing demonstrated that one of the two chemical scaffolds binds to a novel location in the HIV-1 RT p51 subunit, interacting with residue Y183 that has no known association with previously reported drug resistance. This finding leads to the notion of a novel druggable site on p51 for a new class of non-nucleoside RT Inhibitors that may inhibit HIV-1 RT allosterically. Although inhibitory activity was shown experimentally only to be in the hundreds micromolar range, the scaffolds serve as a proof-of-concept of targeting HIV RT p51, with the possibility for medical chemistry methods to be applied to improve the inhibitory activity, towards a functioning drug.

microbiology