Clostridium clariflavum strains as promising bacterial
biocatalysts for lignocellulosic biofuel production
Javier A. Izquierdo, Assistant Professor, Department of Biology, Hofstra
University
ABSTRACT
Our lab uses anaerobic thermophilic bacteria as models for consolidated bioprocessing
(CBP) applications for the production of cellulosic biofuels. Here we describe our
group’s combinatorial approach involving bioprospecting, fermentation science and
genomic exploration to better understand a variety of novel Clostridium clariflavum
strains. Our bioprospecting efforts have now expanded to new inoculum sources within
the state of New York with very promising results. These organisms are comparable
with other leading CBP models for cellulosic biofuel production, such as C.
thermocellum, while overcoming a number of key limitations. Analysis of their genomes
has revealed the mechanisms used by these organisms to break down lignocellulosic
biomass through a unique cellulosomal system and multifunctional glycoside
hydrolases, many of them composed of novel xylanases. These findings explain our
observations in fermentation experiments of 5-carbon polymers that revealed distinctly
different profiles of hemicellulose utilization. We have been able to improve the
performance of C. clariflavum environmental strains through adaptation experiments
resulting in an increase on ethanol yields. In this talk, we will also discuss the ability of
these microbes to utilize real-life biofuel crops, with a focus on unpretreated switchgrass
and shrub willow under different levels of pretreatment.
BIOGRAPHY
Dr. Javier A. Izquierdo is an Assistant Professor in the Department of Biology at Hofstra
University. Research in Dr. Izquierdo's lab explores the metabolic diversity of microbial
processes and the applications we can derive from them. He utilizes cross-disciplinary
approaches incorporating microbiological, ecological, evolutionary, molecular and genomic
techniques to 1) understand beneficial plant-microbe interactions promoting plant growth and
health to explore their uses in agriculture and 2) discover novel microbial metabolic capabilities
that can be turned into biotechnological applications for the production of biofuels. Dr. Izquierdo
holds a B.Sc. in Biology from Case Western Reserve University and a Ph.D. in Microbiology
from the University of Massachusetts Amherst.
th
8 Annual NYS Biotechnology Symposium
- May 19 & 20, 2016 -