When I think of Hanspaul Hagenmaier, it feels like remembering an elder brother. As his first doctoral student (1969–1972) after his habilitation, I recall long evenings spent in front, beneath, or inside of a home-made ion-exchange chromatographic set-up, constructed from pieces and scrap parts of an early commercial version of a Stein and Moore apparatus for amino acid analysis, conceived about a decade earlier and for which the latter two received the Nobel Prize in 1972, just when I was finishing my doctoral thesis. Hands purple from ninhydrin, we struggled with leaking pumps, irregular buffer or reagent delivery systems, and fading thermostats. However, the inspiration and untiring devotion typical of HH – as we conveniently referred to him between us students – kept me going, as did his drive to get things done as soon as possible, even though it took until late at night. We experimented with ion exchangers of different functionalities, crosslinking, and particle sizes, tested the elution behavior of home-synthesized oligopeptides of various lengths, and tried to separate amino acid sequence variants of partial sequences of calcitonin, the solid-phase synthesis of which was the topic of my doctoral work. The problem of truncated and failure sequences in solid-phase peptide synthesis was at that time extensively studied by HH and Ernst Bayer, then Director of the Chemical Institute at the University of Tübingen. The latter had appointed HH in 1965 to help in establishing a strong group in peptide synthesis. HH and I were proud of our early “high-performance liquid chromatography” system, although our publication on “Molecular sieve effects in ion exchange chromatographic separations of oligopeptides” in the Journal of Chromatography did not receive much attention, but this was compensated for by the encouraging words of the late Istvan Halasz on his visit to Tübingen (together with the young Heinz Engelhardt). More successful were our studies on the peptide bond-forming coupling reaction, work which we had first attempted to publish – unsuccessfully – in Angewandte Chemie but which later appeared in Hoppe-Seylers Zeitschrift für Physiologische Chemie as “Increased coupling yields in solid-phase peptide synthesis with a modified carbodiimide coupling procedure” which turned out to become the second most cited paper in HH's list of about 140 publications.
When we met again for the presentation of some of our work at the Fourth American Peptide Symposium in November 1974 in New York (I coming from Houston, Texas, where, in the meantime, I was working as a postdoc with Dominic Desiderio in the Institute of Lipid Research of the late Evan Horning at the Baylor College of Medicine) I got to know and enjoy HH's familiarity and fondness of the USA and of this city (New York) in particular, especially when he introduced us to the marvels of China Town on Canal Street. His affectionate relationship to New York stemmed from the (obviously) happy times HH must have spent there. Born on 31 December 1934 and grown up in the profoundly Swabian, small town of Geislingen, he studied chemistry at the University of Tübingen. However, immediately after having completed his thesis with the late Eugen Müller in 1961, his appetite for new worlds led him to continue studying biochemistry at the Cornell Medical School in New York where he finished his PhD with Nobel Laureate Vincent du Vigneaud in 1965, and later to spend another year in the USA in 1971 with Nobel Laureate Christian B. Anfinsen. However, perhaps, most important might have been that here he met and married Marianne in 1962.
Marianne – the complement to HH – was the stabilizing and pivotal point of his life. She frequently came to the laboratory, even worked with us for a while, chatted with us, and gave him – and us – the freedom to enjoy the pleasures of combining work in the laboratory with the social activities a small Swabian town with a large, old university could offer, like evenings in the so-called “broom-pubs” (Besen-Wirtschaften), temporary establishments to give students and their tutors a chance to sample the bubbling, still fermenting new wine shortly after the grape harvest in October, or getting together in his house to watch the TV transmission of the famous battle between Cassius Clay, or Mohamed Ali, as he started to call himself at that time, and Joe Frazer on 8 March 1971. As this fight took place in the evening in Madison Square Garden, New York, due to the time-zone difference we had to stay awake – once in a while falling asleep on the sofa – until early morning, but with her untiring hospitality Marianne kept us happy. HH was a fervent supporter of Cassius Clay, and when the battle was lost, we all felt quite sad with him. It can only be imagined how hard it is now for Marianne to carry on without HH.
Because of HH's expertise in both organic chemistry and biochemistry, he had wide scientific interests, not only in peptide synthesis, but also in other fields of natural products chemistry, especially in structure elucidation of antibiotics by mass spectrometry and nuclear magnetic resonance (NMR), so the paper published jointly with Bayer, Gugel, Hägele, Jessipow, König, and Zähner on phospinothricin is the most cited publication on his list, but later studies on bafilomycin and nikkomycin received similar, wide attention. In his teaching, HH presented chemistry, stereochemistry, and analytical techniques to biochemistry students. This, in some way, also triggered my interest in stereochemistry and in practical analytical methods at the time of my coming back from the USA in August 1976 to join Bayer's group for a year before I started to venture into chemical toxicology.
At about the same time, HH started to turn his interest to environmental-chemical studies, as pollution problems received increasing public attention and funding became available for such issues. At first, HH's motivation might have been to secure a good share of the research money. However, he utilized such resources to his best advantage, and it took him only a short while to contribute fundamentally to this field as well. Together with Peter Krauss, he helped conceive the first legal threshold pollution limit values for metals, only to soon turn his interest to an even more problematic issue of that time, the widespread environmental occurrence of the dioxins, the congeners of the highly toxic 2,3,7,8-tetrachlorodibenzodioxins publicly discussed since the Seveso accident in 1974, and especially since they had been discovered by Otto Hutzinger in the flue gas and fly ash of waste incineration plants. HH's contributions spanned from development of highly efficient trace-analytical methods, tracing the origins and ways of dioxin formation during incineration, their environmental distribution and fate in various matrices, designing practical, technically-feasible methods for their catalytic destruction, all the way to toxicological-metabolic and risk-assessment studies. As HH was entering the same area and was of similar age to the late Otto Hutzinger – my predecessor at the University of Bayreuth (who passed away just half a year earlier; see John Giesy's obituary in Toxicological and Environmental Chemistry 94: 2060–2064) – constructive competition and occasional scientific disagreement were a natural consequence of their different personalities and scientific provenance. While Otto Hutzinger was an established authority on dioxins since the 1970s, had founded several journals including this one, and had initiated the dioxin conferences the first of which took place in Rome in 1980, HH entered the dioxin field just at that time. However, as to be expected, his fame in this field rose rapidly, especially after the publication of two highly cited papers in 1987, reporting his discovery that copper is involved in the catalytic formation of dioxins in waste-incineration plants, and that the same principle can be exploited for their degradation, using also other transition metals. His finding was an important scientific achievement that contributed in a ground-breaking manner to bring the emotional public brawl about the “poison slings” to a rational, scientifically based dialogue. Thus, HH became widely recognized as a dioxin expert, was a frequent speaker at international conferences, and was decorated with various scientific and civil awards such as the Clean-Technology Award of the European Union (1987) or the Federal Cross of Merit of Germany (1988). But, untiring as he was, HH's interest then turned further to the xenoestrogens, the field in which he published his last major papers early in the new century; these are also highly cited today, more than 10 years later. Then, around 2000, he retired from the laboratory and active scientific pursuit.
HH was – and is – an exemplary scientist who enjoyed the chemical science in its full range, not only its intellectual side, but also all its social and human aspects. He did not only reside in an academic ivory tower, but always looked for ways to contribute his potential and possibilities for the well-being of those around him. He kept his promises and was steadfast in his relations. Thus, HH's contact with his many coworkers always remained amiable, so they celebrated with him their memories in regular annual get-togethers – until HH left suddenly, unexpectedly, on 13 March 2013. HH was a wonderful colleague and mentor who will be remembered for a long time.