Otto Kandler

Otto Kandler was born on 23 October 1920 in Deggendorf, Bavaria, as the 6th child of the family of a market gardener. Growing up and helping in his father's garden, early on, he became interested in plant life and nature in general. He attended school for 8 years. When he was about twelve years old he had read about Charles Darwin and mentioned it to a Catholic priest. The priest punished him with two strikes on his hands with a rod. However he remained interested in the origin and evolution of organisms for the rest of his life. he received a generous research fellowship from the Rockefeller Foundation and, in 1956/1957 he was able to work on basic questions of photosynthesis for one year in the USA. His broad scientific interests are indicated by the titles of his more than 400 publications. His scientific legacy was handed over to the university archive of the LMU. Kandler would have celebrated his 100th birthday on 23 October 2020. For this centenary Kandler's family gave his chronological collection of historical botany books, among them herbals of the 16th and 17th centuries, as a present to the library of the "Regensburgische Botanische Gesellschaft" (founded by David Heinrich Hoppe in 1790), which has been included in the library of the University of Regensburg. Through digitization these historical sources soon will be generally accessible. ==Plant physiology==

Otto Kandler was very interested in plant growth processes, photosynthesis, metabolism, especially of carbohydrates. As the first in Germany he started to grow isolated plant tissue cultures (e.g. of stems, roots, sprouts, embryos, callus growths) in vitro to study metabolism and the effect of auxins under defined in vitro conditions. As mentioned above, this formed the subject of his dissertation (summa cum laude) in 1949. In his contribution „Historical perspectives on queries concerning photophosphorylation" Kandler describes the beginnings of photophosphorylation research and how he became interested: In 1948, he was inspired by a lecture on the phosphate metabolism of yeast by Feodor Lynen (1964 Nobel Prize in Physiology or Medicine). In these years, in the aftermath of World War II, the original Chemical Institute of the Ludwig-Maximilians-Universität München (LMU) was still in ruins and Feodor Lynen and his assistant Helmut Holzer were working temporarily as guests in the Botanical Institute just next door to the laboratory where Kandler was engaged in his thesis in botany. Kandler was impressed by the experimental methods in Lynen's laboratory and got acquainted with them; Holzer and Kandler became close friends. Kandler then decided to transfer their techniques for measuring phosphorylation rates in vivo to photosynthesis studies in Chlorella. So, in 1950, he was the first to present experimental evidence for the light-dependent formation of ATP (photophosphorylation) in vivo in intact Chlorella cells. and mentioned Kandler's pioneering work. Kandler's early publications on light-dependent formation of ATP and then for another 6 months with Melvin Calvin (1961 Nobel Prize in Chemistry) at the University of California, Berkeley on central questions of photosynthesis (e.g. the path of carbon in photosynthesis, today called the Calvin-Benson-Bassham Cycle). The method of radioactive labelling, i.e. the use of radioactive isotopes for tracing the path of e.g. carbon in photosynthesis, was brought to Germany by Kandler. Together with his coworkers, Kandler demonstrated the occurrence of ADP-glucose, the glucose donor of starch biosynthesis, for the first time in plants. He made an essential contribution to clarify the complicated biosynthesis of branched-chain monosaccharides (hamamelose, apiose). Finally he elucidated the biosynthesis of the sugars of the raffinose family, the most frequent oligosaccharides in plants. As a result of these findings, the function of galactinol, a galactoside of inositol, as a galactosyl donor, was elucidated, and hence the role of inositol as a co-factor of sugar transfer reactions in plants. ==Microbiology==

In addition to his interest in plant physiology and biochemistry Otto Kandler early on focused on bacteria, above all, on the presence or absence of their cell walls, since, in the early 1950s, such wall-less microorganisms were often regarded as representatives of "urbacteria". These publications are still cited at present. During his time as director of the Bacteriological Institute of the South German Dairy Research Center in Freising-Weihenstephan, Kandler concentrated on dairy microbiology and investigated the physiology, biochemistry and systematics of lactobacilli, on which he wrote a chapter in Bergey's Manual, the ‘bible' of microbiologists. Kandler’s cell wall studies also included methanogenic "bacteria" (methanogens) and halophilic "bacteria" (halophiles). In October 1976 Kandler discovered that two strains of the methanogen Methanosarcina barkeri did not contain peptidoglycan. Consequently, he came to the conclusion that methanogens are basically different from bacteria. In his group, also "halobacteria" were found to lack peptidoglycan, confirming the idea, that also these organisms are not bacteria and belong to a group of organisms soon called "archaebacteria" (in 1990 classified as archaea The methanogen Methanopyrus kandleri was named in honor of Kandler by Karl O. Stetter as a present for Kandler's 70th birthday. Together with Hans Günter Schlegel, Kandler was substantially involved in the foundation of the German collection of microorganisms and cell cultures (DSMZ) in Braunschweig. Kandler was the founder and editor of Systematic and Applied Microbiology, co-editor of the Archives of Microbiology and of Zeitschrift für Pflanzenphysiologie. ==Archaea and the three domains of life==

Otto Kandler's main subject in microbiology was his research on archaea (before 1990 called "archaebacteria"). His discovery (October 1976) that peptidoglycan (murein), a typical cell wall component of bacteria, is missing in two strains of methanogenic "bacteria" (methanogens) that methanogens belong to a group of organisms distinct from bacteria. Therefore, Kandler was delighted when he learned from a letter by Ralph F. Wolfe, expert on methanogens, on 11 November 1976, that Wolfe's colleague Carl Woese (University of Illinois, Urbana, USA) had just discovered basic differences between methanogens and bacteria with his novel 16S ribosomal RNA gene sequencing method. When Kandler received this letter, based on his new findings, he had already planned to investigate the cell walls of other methanogens together with Marvin P. Bryant, also an expert on methanogens from the University of Illinois. Coincidentally, Bryant was just sitting in Kandler's office when Wolfe's letter arrived. – in the US, Kandler called Woese "the Darwin of the 20th century" The first international conference ever on "archaebacteria" was also organised by Kandler, again in Munich, in 1981. Both, Carl Woese and Ralph Wolfe took part. The resulting conference volume was the very first book on "archaebacteria". At this conference convincing evidence for essential structural, biochemical and molecular differences between bacteria and "archaebacteria" was presented leading to the gradual acceptance of the concept of the "archaebacteria" as an autonomous group of organisms. After the conference, the "archaebacteria" were celebrated by Woese, Wolfe and Kandler on an excursion to the close Alps climbing the top of Hochiss (2299 m) in the Rofan mountains (see Photos). (2009, especially chapters 19, 20). Woese and Kandler proposed a "tree of life" consisting of three lines of descent (see adjacent "Phylogenetic Tree of Life") for which they introduced the term domain as the highest rank of classification, above the kingdom level. They also suggested the terms Archaea, Bacteria and Eucarya (later corrected to Eukarya) for the three domains and presented the formal description of the taxon Archaea. Up to date, this publication is one of the most frequently cited papers in the Proceedings of the National Academy of Sciences of the United States of America. (The role of the third author is described by Sapp (pp. 261f. and 386)) In a second publication, they contrasted their natural system of "global classification", a phylogenetic division on the basis of 16S rRNA sequencing, with the conventional division of organisms into two (procaryotes-eucaryotes system) or into five (5-kingdom system) groupings. Today the division of the tree of life into three domains – levels above kingdoms – is textbook knowledge. == Early evolution and diversification of life (pre-cell theory) ==

Kandler has always been interested in the early evolution and diversification of life and, finally, presented his pre-cell theory. 2003{{cite journal| last = Wächtershäuser| first = Günter Schleifer 2011. == Applied Microbiology ==

Louis Pasteur was one of Kandler's scientific heroes. Kandler liked to cite Pasteur's opinion that there is no "applied science", but that there are rather "applications of science". When he was director of the Bacteriological Institute of the South German Dairy Research Center in Freising-Weihenstephan, he concentrated on the microbiology of milk and dairy products, e.g. developed methods to prolong the shelf-life of milk, and tested the utilisation of Lactobacillus acidophilus in starter cultures for yoghurt. He also tested several procedures for the fermentation of milk and vegetable products or proposed methods for successfully combating micro-organisms in cooling water systems (more examples see Schleifer 2011. Later he conducted research on thermophilic methanogens and their ability to produce biogas from sewage or other waste. ==Ecology==

Kandler's role as an early representative of scientific ecology is less known. He was a cofounder of the "commission for ecology" at the Bavarian Academy of Sciences (now "Forum für Ökologie" – panel for ecology{{cite web of which he was a member until 2006. His interest in ecology was broad; for instance he dealt with bacterial interactions, forest conditions and the return of lichens into the city of Munich.{{cite journal | last1 = Kandler | first1 = Otto| author-link1 = Otto Kandler | last2 = Poelt | first2 = Josef| title = Wiederbesiedlung der Innenstadt von München durch Flechten Since the early 1980s, research on the so-called "Waldsterben" (forest death) in Germany was substantially sponsored by the German Ministry of Science and Technology. On the basis of his own investigations,{{cite journal Kandler became a decided critic.{{cite journal ==Awards and memberships==

• 1971 German National Academy of Sciences Leopoldina • 1981 Dr. h.c. (Ghent University) • 1982 Regensburger Botanische Gesellschaft • 1982 Bergey Award • 1983 Bavarian Academy of Sciences and Humanities • 1983 Mycological Society of India • 1984 Hermann Weigmann-Medaille • 1985 Dr. h.c. (Technical University of Munich) • 1989 Ferdinand-Cohn-Medaille • 1991 Honorary member of Deutsche Botanische Gesellschaft • 1992 Order of Merit of the Federal Republic of Germany • 1994 Honorary member of Gesellschaft für Allgemeine und Angewandte Mikrobiologie • 2005 Bavarian Order of Merit ==Selected publications==

• Kandler, Otto (1950). Über die Beziehungen zwischen Phosphathaushalt und Photosynthese: I. Phosphatspiegelschwankungen bei Chlorella pyrenoidosa als Folge des Licht-Dunkel-Wechsels. [On the relationship between the phosphate metabolism and photosynthesis I. Variations in phosphate levels in Chlorella pyrenoidosa as a consequence of light-dark changes]. Zeitschrift für Naturforschung 5b, 423–437 pdf. • • • • • • • • • • Kandler, O. (1998). The early diversification of life and the origin of the three domains: A proposal. pp. 19–31. In: Thermophiles: The keys to molecular evolution and the origin of life? (J. Wiegel & M.W. Adams eds.) Taylor and Francis Ltd. London, UK googlebooks • • all publications: BAdW ==Biographies and obituaries==

• Müller, H.E. (1998). Portrait: "Otto Kandler und die moderne Mikrobiologie". Der Mikrobiologe. Mitteilungen des Berufsverbands der Ärzte für Mikrobiologie, Virologie und Infektionsepidemiologie 8(3), 38–43 BAdW. • Sapp, J. (2009). The New Foundations of Evolution: On the Tree of Life. Oxford, New York: Oxford University Press. googlebooks. • (Bergey's International Society for Microbial Systematics) BAdW. • Tanner, W. (23 November 2017). Obituary: Professor Dr. Otto Kandler (1920–2017). Deutsche Botanische Gesellschaft . • (typo in abstract: the three forms of life are Bacteria, Archaea, Eukarya). • Tanner, W.; Renner, S. (September 2018). Obituary - Prof. Dr. Dr. h.c. mult. OTTO KANDLER BAdW • for further reading BAdW. ==References==