The plant cell wall, and cellulose in particular, comprises the most abundant source of organic carbon on the planet and its utilization is of considerable biological and industrial importance. Indeed, the microbial degradation of cellulose and other plant structural polysaccharides is critical to the maintenance of both marine and terrestrial life. The plant cell wall represents an extremely challenging substrate that is comprised of a complex web of interlocking polysaccharides, polyphenolics, and polypeptides. Thus, microbial enzyme systems that attack the plant cell are presented with a considerable physical access problem. Indeed, the major plant polysaccharide hydrolases are ~1000-fold more active against soluble forms of their substrates than when they are embedded within the plant cell wall. Consequently, the plant cell wall degrading apparatus of microorganisms typically consists of between 100 and 300 different enzymes which, in addition, often display a complex molecular architecture to ensure tight association with its macromolecular substrate.
The study of plant cell wall degradation, which initially focused on cellulases and cellulose saccharification, began in earnest in the 1950s, principally through the study of the aerobic fungus Trichoderma reesei
and other ascomycetes. Our knowledge of these enzymes expanded into the prokaryote world shortly after and led to the discovery of cellulosomes in the 1980s, which are supramolecular complexes of (predominantly) cellulases and other carbohydrate-active enzymes present on the cell surface of many anaerobic prokaryotes that specialize in plant biomass degradation. The field of cellulases and cellulosomes has developed rapidly, enabled by advances in molecular biology, genetics and structural biology. Indeed, the significant advances made in the 1990s - which have continued unabated into the 21st century - motivated the first GRC on Cellulases and Cellulosomes held in 1999 at the Proctor Academy, New Hampshire. The Chairs for the inaugural meeting were David Wilson and Edward A. Bayer, both pioneering scientists in the molecular dissection of cellulases and cellulosomes, respectively.
While the enzymes that attack cellulose are already widely used in several biotechnology-based industries, the major future application of these biocatalysts is the conversion of plant biomass into biomaterials, organic chemical feedstocks, and liquid fuels. In this context, the Conference presents the latest breakthroughs in our understanding of the enzymology, structural biology and (meta)genomics underpinning the modification of plant structural polysaccharides and their conversion into fermentable sugars, both in natural and engineered processes. In addition to cellulases and cellulosomes, there is an increasing emphasis in recent conferences on the roles of other carbohydrate-active enzymes in plant biomass conversion, which was reflected in a change of the title of this GRC to "Cellulosomes, Cellulases and other Carbohydrate Modifying Enzymes" in 2009.
The scientific sessions include aspects of the biophysical and structural analyses of native and chemically pretreated plant biomass and component polysaccharides; functional and comparative analyses of carbohydrate binding modules and enzyme-substrate interactions; crystallographic and biochemical analyses of enzyme structure and function; molecular mechanisms underpinning enzyme catalysis, processivity and specificity; directed evolution for the development of catalytically superior glycoside hydrolases; genomics of specialist polysaccharide degrading microbes; metagenomics and ecophysiology of plant biomass degradation in natural and engineered processes; and enhancement of industrial bioprocesses by protein engineering, metabolic engineering and related approaches.
Since its inception, this GRC has consistently attracted more than 100 scientists per meeting, and is truly international, with typically more than half of the participants traveling from outside North America to attend. In keeping with this international spirit, the Conference has a tradition of electing its chairpersons alternately from Europe and North America. In addition to the leadership provided by preeminent scientists, more than half of the participants at previous conferences were in their 30s and 40s, ensuring the Conference maintains a vibrant and well balanced participation of junior and senior researchers. Specific emphasis is placed on the active participation of postdoctoral and senior graduate students, who are routinely invited to give oral presentations, in addition to presenting their work in traditional poster sessions. In 2011, an associated Gordon Research Seminar was inaugurated to help these new and young researchers maximize their contributions to, participation in, and inspiration from the GRC.
While the conference draws many of its participants from academia and government agencies, colleagues from industry have made many important and valuable contributions to the success of all the conferences. The conference provides a stimulating environment for discussion between all scientists through an active social program, and the provision for extended afternoon discussion sessions. This makes the conference a truly interactive and productive venue for all sectors interested in the fundamental and applied aspects of plant cell wall degradation.
What is a GRC? Gordon Research Conferences (GRC) are 5-day meetings that bring scientists together from around the world to present and discuss unpublished research with other leaders in their field.