Professor, Constellation Chair
Professor Gross received his Ph.D. from 'Brooklyn Poly' (Polytechnic University) working on Polymer Stereochemistry (synthetic chemistry) and then performed postdoctoral research with Robert Lenz at UMASS Amherst on the synthesis/properties of polyhydroxyalkanoates (i.e. bacterial polyesters).
His research is motivated by the urgent need to develop sustainable chemicals and materials to meet the demands of a rapidly rising global population while mitigating risks of increased green-house gas emissions asociated with climate change. Gross is focusing the groups inventiveness on research that has the potential to revolutionize the way we synthesize next-generation chemicals and materials as well as improve human health. For this purpose, the group is combining the best chemical and biocatalysts to develop efficient green routes to low molar mass molecules, polymers and materials. He is also applying green chemistry principles to develop next-generation therapeutics. For this, we look to nature for tailorable bioactives and use a variety of tools to create matrices for tissue engineering and bioresorbable biomaterials. The result of our emphasis on implementing green chemical principles is the development of synthetic routes that operate under mild reaction conditions (e.g. low temperature, ambient pressure, avoid toxic reagents) that increase worker safety, improve reaction efficiencies (i.e. atom economy) while avoiding protection-deprotection steps. By working this way we increase the chance that we develop will be scalable and used.
Examples of ongoing research are as follows. There is a need to develop efficient and scalable methods to synthesize peptides. These building blocks hold great promise for creating antimicrobial, metal binding, self-assembling, bioadhesives (to replace sutures) and environmentally responsive materials. However, peptide synthesis currently relies on solid and liquid phase methods (SPPS and LPPS) that are expensive and, consequently, prohibit the use of peptides in these and other exciting fields of application. Our laboratory is pioneering methods that use protease-catalyst to build peptides in aqueous media without the need for protection-deprotection steps. Protease-catalyzed peptide synthesis allows scale-up of peptide building blocks for a wide range of exciting material applications. In other work, we are using the selectivity of lipase catalysts to synthesize functional bioresorable polyesters that meet important needs for tissue engineering matrices, drug delivery systems and bioactive materials. Another focus area is the use of bacteria that directly extrude cellulose nanofibers from cell membranes that become intertwined creating interconnected nanofiberous 3-D matrices. One aim in this program is to control matrix parameters including fiber size and porosity to tailor bacterial cellulose for applications as membranes for separation/water purification, reservoirs for liquid crystals that form voltage regulated switchable windows and much more. Also, our laboratory is looking to nature for next-generation bioactive compounds (e.g. anticancer, antimicrobial, immunomodulators, insecticides and tick repellents). This work makes use of a family of surface active microbial synthesized glycolipids that can be molecularly engineered to enhance their physical and biological properties. In addition, we are using essential oils and their components as potent/renewable/safe pesticides, insecticides and tick repellents. Some of these antimicrobial components are finding their way into a new family of adherent films that protect fruits and vegetables from premature spoilage. Emulsion and encapsulation technologies are being used to effectively apply or deliver these natural bioactives. Another group project is motivated by the problem of plastic pollution. It is now evident that seperating plastic wastes and physical recycling of recovered plastics has largely failed to create effective pathways for plastic re-use. While our group is interested in the overall potential of biorecycling, work thus far has focused on a family of enzymes known as cutinases that actually degrade plastic water bottles made from PET to their constituent building blocks (terephthalic acid and ethylene glycol).
Our ability to engage in this large array of project areas is possible due to our belief that thet best work is done through productive collaborations with scientists and engineers that bring new perspectives and expertise. Consequently, we have developed productive long-term collaborations with physicists, biologists, biomedical engineers, entomologists, mechanical engineers and process engineers.
Gross has about 500 publications in peer-reviewed journals that have been cited over 26,000 times (h-index 82, i10-index 362). He has graduated over 40 Ph.D. students who are enjoying successful carreers in industry and acedmics. In addition, he believes in the formula of having Ph.D. students active in mentoring as well as working in teams with undergraduate and high school students.
Ph.D. Polytechnic University (Major: Chemistry). Multistep synthesis and studies of chiral helical rigid-rod polymers.
Postdoctoral Research (University of Massachusetts Amherst). Flexibility in the synthetic pathway to microbial polyesters.
- Liu, Fei; McMaster, Michael; Mekala, Shekar; Singer, Kenneth; Gross, Richard A. (2018) Grown Ultrathin Bacterial Cellulose Mats for Optical Applications, Biomacromolecules, Ahead of Print. DOI:10.1021/acs.biomac.8b01269.
- Mekala, Shekar; Peters, Kyle C.; Singer, Kenneth; Gross, Richard (2018) Biosurfactant-functionalized porphyrin chromophore that forms J-aggregates, Organic & Biomolecular Chemistry, (2018), 16(39), 7178-7190. DOI:10.1039/c8ob01655k
- Shirke, Abhijit N.; White, Christine; Englaender, Jacob A.; Zwarycz, Allison; Butterfoss, Glenn L.; Linhardt, Robert J.; Gross, Richard A. (2018) Stabilizing Leaf and Branch Compost Cutinase (LCC) with Glycosylation: Mechanism and Effect on PET Hydrolysis. Biochemistry (2018), 57(7), 1190-1200. DOI:10.1021/acs.biochem.7b01189
- Totsingan, Filbert; Centore, Robert; Gross, Richard A (2017) CAL-B Catalyzed Regioselective Bulk Polymerization of L-Aspartic Acid Diethyl Ester to α-linked Polypeptides Chemical Communications, 53, 4030 -4033 DOI: 10.1039/C7CC01300K
- Koh, Amanda; Gross, Richard (2016) “Molecular editing of sophorolipids by esterification of lipid moieties: Effects on interfacial properties at paraffin and synthetic crude oil-water interfaces” Colloids and Surfaces, A: Physicochemical and Engineering Aspects 507, 170-181.
- Fiorani, Andrea; Totsingan, Filbert; Pollicino, Antonio; Peng, Yifeng; Focarete, Maria Letizia; Gross, Richard A.; Scandola, Mariastella (2017), “Peptide Modified Electrospun Glycopolymer Fibers” Macromolecular Bioscience 17(3) 10.1002/mabi.201600327
- Maiorana, Anthony; Reano, Armando F.; Centore, Robert; Grimaldi, Marina; Balaguer, Patrick; Allais, Florent; Gross, Richard A. (2016) “Structure property relationships of biobased n-alkyl bisferulate epoxy resins” Green Chemistry 18(18), 4961-4973.
- Todd, Richard; Tempelaar, Sarah; Lo Re, Giada; Spinella, Stephen; McCallum, Scott A.; Gross, Richard A.; Raquez, Jean-Marie; Dubois, Philippe Poly(ω-pentadecalactone)-b-poly(L-lactide) Block Copolymers via Organic-Catalyzed Ring Opening Polymerization and Potential Applications ACS Macro Letters (2015), 4(4), 408-41
- Shirke, Abhijit N.; Basore, Danielle; Holton, Samantha; Su, An; Baugh, Evan; (2016) Butterfoss, Glenn L.; Makhatadze, George; Bystroff, Christopher; Gross, Richard A. Influence of surface charge, binding site residues and glycosylation on Thielavia terrestris cutinase biochemical characteristics Applied Microbiology and Biotechnology 100(10), 4435-4446.
- Peng, Yifeng; Totsingan, Filbert; Meier, Michael A. R.; Steinmann, Mark, Wurm, Frederik; Kho, Amanda; Gross, Richard A. “Sophorolipids: Expanding structural diversity by ring-opening cross-metathesis” European Journal of Lipid Science and Technology (2015) 117(2), 217-228.