In memoriam Olav Keerberg (17.04.1935-02.11.2015)
Last month, the eldest member of our work group, Olav Keerberg, who recently turned 80, passed away.
Olav was an emergent figure among Estonian plant physiologists, leading way in studies of photosynthesis. He started the research on chlorophyll chemistry in the Experimental Biology Institute in Harku right after graduating University of Tartu in 1957 as a theoretical physicist. His first research challenge was to design and build precise instruments for measuring photosynthesis using 14C-based methods. Olav´s contribution in designing and building unique photosynthesis measuring instruments was essential. It was now possible to expose leafs to the full range of time and environmental conditions span in order to get the whole picture of regulatory processes controlling the assimilation of carbon in plants. Moreover, under his direction, novel methods of isolating and identifying the intermediary products of photosynthesis, based on chromatography and electrophoresis were implemented. For these measurements, Olav´s work group also designed and built unique instruments.
Most of these methodological and equipmental breakthroughs took place on late 60s and early 70s, and based on these advances, Olav defended his Candidate of Sciences degree (equal to PhD) in 1972 and his Doctor of Sciences (equal to Habilitation degree) in 1989. Olav´s advances were also rewarded with national research prize of Estonian SSR in 1982. Due to large interest regarding these methods, Olav entered into many research connections with the Western researches even during the soviet times; not to mention numerous collaborations with the eastern bloc researchers. After the collapse of USSR, collaborational links between the biochemistry lab in Harku and foreign research institutions deepened even more, especially with colleagues in Umeå, Sweden. All this hard work was complimented by international recognition in the photosynthesis research community.
Since the regaining of Estonian independence, Olav was the PI in eight comprehensive research projects, leading the research in various issues, including the effect of cold shocks on plant respiration and photosynthetic metabolism; differences in photosynthetic metabolism and respiration in C3 and C4 plants; enzyme expression regulation among genetically modified plants and so on. Thus, his main research focus in last couple of decades was on plant metabolomics. Most of his results were published in the top journals of photosynthesis, like Photosynthesis Research, Plant Physiology and Plant, Cell Environment. His last scientific contribution was published in July 2014 in Journal of Experimental Botany: “C2 photosynthesis generates about 3-fold elevated leaf CO2 levels in the C3-C4 intermediate species Flaveria pubescens” (link to full text). Olav was actively carrying out research until the very end, and many of his manuscripts in-progress will hopefully be completed by his colleagues.
Olav was peaceful on composed person, whose poised and insightful comments often resolved the tensions among colleagues. His poised but persistent nature together with effective work rate and dedication enabled him to stay in top science for nearly 60 years. May he inspire us all!
Tiit Pärnik and Ülo Niinemets