
Exploring the flexibility of bacterial polyester synthetic pathways
During his postdoc with Prof. Lenz at UMASS Amherst, and during his early years as a faculty member at UMASS Lowell, Prof. Gross explored the promiscuity of bacteria that synthesize microbial poly(b-hydroxyalkanoates). This work, conducted in parallel to that by Prof. Y. Doi (Riken Univ., Japan), demonstrated that bacterial polyesters can be prepared in a wide variety of structural forms due to the remarkable promiscuity of enzymes involved in poly(b-hydroxyalkanoates) synthesis. Microbial polyesters were prepared with a large number of non-natural repeat units. Examples of new pendant groups or b-substituents incorporated into polymers include cyano- and nitro-phenoxy, highly fluorinated and unsaturated moieties. The first studies that explored the physical and thermal properties of medium-chain length microbial polyesters were reported by Prof. Gross while at UMASS Amherst. Furthermore, deuterated substrates fed to microbial polyester producing organisms provided valuable information on metabolic pathways involved in polyester synthesis.
References
- Richard A. Gross, Oh-young Kim, Denise R. Rutherford and Richard A. Newmark, “Cyanophenoxy-Containing Microbial Polyesters: Structural Analysis, Thermal Properties, Second Harmonic Generation and In-Vivo Biodegradability”, Polym. International, Vol. 39, 205-213 (1996).(PDF)
- Oh-young Kim, Richard A. Gross and Denise R. Rutherford, “Bioengineering of Poly(β-hydroxyalkanoates) for Advanced Material Applications: Incorporation of Cyano- and Nitrophenoxy Side Chain Substituents”, Can. J. Microbiol., Vol. 41, supplement 1, 32-43 (1995).(PDF)
- Fengying Shi, Richard D. Ashby and Richard A. Gross, “Formation by Alcaligenes species of Microbial Polyesters Containing 3-Hydroxybutyrate and 4-Hydroxybutyrate Repeat Units: Investigation of Product Homogeneity”, Macromolecules, Vol. 30, 2521-2523 (1997).(PDF)
- Oh-young Kim, Richard A. Gross, W. James Hammar and Richard A. Newmark, “Microbial Synthesis of Poly(β-hydroxyalkanoates) Containing Fluorinated Side-Chain Substituents”, Macromolecules, Vol. 29, No. 13, 4572-4581 (1996).(PDF)
- Herbert W. Ulmer, Richard A. Gross, Mario Posada, Paul Weisbach, R. Clinton Fuller and Robert W. Lenz, "Bacterial Production of Poly(β-hydroxyalkanoates) Containing Unsaturated Repeating Units by Rhodospirillum rubrum, Macromolecules, Vol 27, 1675-1679 (1994).(PDF)

