Umakant Waman Kenkare earned his BSc (1949) and MSc (by research) in Biochemistry (1952). He did his PhD on "Studies in Folic Acid Metabolism" under the guidance of Professor BM Braganza from Bombay University. Subsequently, he went to USA to join Professor SP Colowick of the Vanderbilt University for post-doctoral training. He, along with Colowick, demonstrated the complete reversibility of protein denaturation and its importance for showing the primacy of protein sequence for 3-D structure of a protein. In 1963, Kenkare joined Professor FM Richards at Yale University, New Haven, Connecticut and established that ribonuclease S had the same structure in solution and in crystalline states, and that the active site histidyl residues 12 and 119 had only a catalytic role and no structural role. On return to India (1965), Kenkare joined the Molecular Biology unit of Tata Institute of Fundamental Research (TIFR). He retired from TIFR (1987) and shifted initially to Delhi University South Campus and thereafter to National Tissue Culture Facility in Pune as a CSIR Emeritus Scientist.
Academic and Research Achievements: Kenkare taught protein biochemistry at TIFR, Bombay and at the Universities of Pune and Delhi. At TIFR, he initiated a programme of studies on structure, function and regulation in enzymes with a focus on brain mitochondrial hexokinase, known as Type-I isoenzyme of the mammalian hexokinase isoenzyme family of four. The Type-I is a key enzyme for the utilization of glucose in the brain. The enzyme phosphorylates glucose to glucose 6-phosphate in presence of ATP and Mn(II) or Mg(II) ions. The chemical study of enzyme led them to conclude that two thiols, one essential and the other non-essential, are in close proximity at the active site of the enzyme. Kenkare's group, in collaboration with Professor SR Kasturi, discovered two modes of Mn (II) binding to the enzyme, one directly to the enzyme with high affinity and the other through the ATP bridge. The latter participates in catalysis. The glucose and glucose 6-phosphate, when added to the enzyme independently, bind to the active site and his group discovered that there is no pre-existing allosteric site for glucose 6- phosphate on the enzyme, and the site is created on the enzyme only in the presence of glucose. He has published about 40 papers and guided 7 PhD and 4 MSc students. Kenkare, in association with Professor KS Krishnan of the Molecular Biology group, initiated studies in Neurochemistry and Membrane Biology. They identified two glutamate transport systems in well characterized Drosophila synaptosomes L-aspartate. Inhibitors of glutamate transport in mammalian brain preparations also inhibited the Drosophila system. They also explored the enzyme phospholipid methyl transferase which is implicated in many membrane events. Kankare, in collaboration with Professor Natarajan of Leiden University, Netherlands, showed that genes coding for Types I, II, III and IV hexokinase isoenzymes are, respectively, located on chromosomes 20, 4, 17 and 14 indicating that these isoenzymes are products of different genes and not of a single gene differently processed in different tissues where they are located. The induction of hexokinase gene expression by insulin like growth factors in brain and cancer cell lines has also been demonstrated.
Awards and Honours: Kenkare is a Fellow of the Indian Academy of Sciences, Bangalore (1986).