Emeritus Professor of Chemistry
Adjunct Professor of Medicinal Chemistry
Adjunct Professor of Microbiology
Ph.D. Technical University Munich, 1961
(Bioorganic and Organic Chemistry)
Work in the Floss laboratory revolved around the application of principles, concepts, and techniques of organic chemistry to solve biochemical and biological problems. The major theme investigated was the biosynthesis of antibiotics and related natural products.
These studies used a combination of genetic, chemical and biochemical approaches to elucidate the biosynthetic pathways, characterized the genetic and biochemical machinery controlling them, and used this knowledge to engineer the production of new, potentially bioactive compounds. The genetic approaches involved the cloning, sequencing, mutational analysis and heterologous expression of antibiotic biosynthesis gene clusters. In parallel, chemical and biochemical approaches involved feeding experiments with isotopically labeled precursors and intermediates, isolation and structure elucidation of new compounds accumulated by specifically constructed mutants, and the characterization and mechanistic analysis of important biosynthetic pathway enzymes. Elucidation of the biosynthetic pathway was followed by genetic reengineering of the encoding biosynthetic gene cluster to alter its catalytic specificity, resulting in new endproducts with modified structures.
S. C. Wenzel, R. M. Williamson, C. Grünanger, J. Xu, K. Gerth, R. A. Martinez, S. J. Moss, B. J. Carroll, S. Grond, C. J. Unkefer, R. Müller, H. G. Floss, "On the Biosynthetic Origin of Methoxymalonyl-Acyl Carrier Protein, the Substrate for Incorporation of "Glycolate" Units Into Ansamitocin and Soraphen A", J. Am. Chem. Soc. 128, 14325-14336 (2006).
B. Srinivasulu, Y. - J. Kim, Y. - K. ChangT. - W. Yu, H. G. Floss, "Construction of asm2 Deletion Mutant of Actinosynnema pretiosum and Medium Optimization for Ansamitocin P-3 Production Using Statistical Approach" J. Microbiol. Biotechnol. 16, 1338-1346 (2006).
Y. Hu, H. G. Floss, "Starter Unit Specificity of the Asukamycin "Upper" Chain Polyketide Synthase and the Branched-Chain Fatty Acid Synthase of Streptomyces nodosus subsp. asukaensis" Heterocycles, 69, 133-149 (2006).
T. Kubota, M. Brünjes, T. Frenzel, J. Xu, A. Kirschning, H. G. Floss, "Determination of the Cryptic Stereochemistry of the First PKS Chain Extension Step in Ansamitocin Biosynthesis by Actinosynnema pretiosum" ChemBiochem, 7, 1221-1225 (2006).L. Bai, L. Li, H. Xu, K. Minagawa, Y. Yu, Y. Zhang, H. G. Floss, X. Zhou, T. Mahmud, Z. Deng, "Functional Analysis of the Validamycin Biosynthetic Gene Cluster and Engineered Production of Validoxylamine A", Chem. Biol., 13, 387-397 (2006).
Elected Honorary Member of the Kitasato Institute, Tokyo
Honorary Doctor of Science Degree, University of Bonn
White Magnolia Commemoration Award and Medal, City of Shanghai
Research Achievement Award, American Scociety of Pharmacognosy
Honorary Doctor of Science Degree, Purdue University