skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Detecting Cellulase Penetration Into Corn Stover Cell Walls by Immuno-Electron Microscopy

Journal Article · · Biotechnology and Bioengineering
DOI:https://doi.org/10.1002/bit.22281· OSTI ID:969729
; ; ; ; ;

In general, pretreatments are designed to enhance the accessibility of cellulose to enzymes, allowing for more efficient conversion. In this study, we have detected the penetration of major cellulases present in a commercial enzyme preparation (Spezyme CP) into corn stem cell walls following mild-, moderate- and high-severity dilute sulfuric acid pretreatments. The Trichoderma reesei enzymes, Cel7A (CBH I) and Cel7B (EG I), as well as the cell wall matrix components xylan and lignin were visualized within digested corn stover cell walls by immuno transmission electron microscopy (TEM) using enzyme- and polymer-specific antibodies. Low severity dilute-acid pretreatment (20 min at 100 C) enabled <1% of the thickness of secondary cell walls to be penetrated by enzyme, moderate severity pretreatment at (20 min at 120 C) allowed the enzymes to penetrate {approx}20% of the cell wall, and the high severity (20 min pretreatment at 150 C) allowed 100% penetration of even the thickest cell walls. These data allow direct visualization of the dramatic effect dilute-acid pretreatment has on altering the condensed ultrastructure of biomass cell walls. Loosening of plant cell wall structure due to pretreatment and the subsequently improved access by cellulases has been hypothesized by the biomass conversion community for over two decades, and for the first time, this study provides direct visual evidence to verify this hypothesis. Further, the high-resolution enzyme penetration studies presented here provide insight into the mechanisms of cell wall deconstruction by cellulolytic enzymes.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC36-08GO28308
OSTI ID:
969729
Report Number(s):
NREL/JA-270-44987; BIBIAU; MainId:48314; UUID:0e330e3b-d1d4-e411-b769-d89d67132a6d; MainAdminId:30406; TRN: US201002%%201
Journal Information:
Biotechnology and Bioengineering, Vol. 103, Issue 3; ISSN 0006-3592
Country of Publication:
United States
Language:
English

References (18)

Structure and Biogenesis of the cell Walls of Grasses journal June 1996
Cell wall porosity and available surface area of wheat straw and wheat grain fractions journal November 1997
Visualizing lignin coalescence and migration through maize cell walls following thermochemical pretreatment journal December 2008
Effect of degradation on the porosity and surface area of forage cell walls of differing lignin content journal January 1999
Porosity and Its Effect on the Digestibility of Dilute Sulfuric Acid Pretreated Corn Stover journal April 2007
Cellulase digestibility of pretreated biomass is limited by cellulose accessibility journal January 2007
Study of Lignification by Noninvasive Techniques in Growing Maize Internodes (An Investigation by Fourier Transform Infrared Cross-Polarization-Magic Angle Spinning 13C-Nuclear Magnetic Resonance Spectroscopy and Immunocytochemical Transmission Electron Microscopy) journal July 1997
How biotech can transform biofuels journal February 2008
Monoclonal Antibodies to Plant Cell Wall Xylans and Arabinoxylans journal April 2005
Features of promising technologies for pretreatment of lignocellulosic biomass journal April 2005
Family 7 cellobiohydrolases from Phanerochaete chrysosporium: crystal structure of the catalytic module of Cel7D (CBH58) at 1.32 Å resolution and homology models of the isozymes journal December 2001
The catalytic module of Cel7D from Phanerochaete chrysosporium as a chiral selector: structural studies of its complex with the beta blocker ( R )-propranolol journal March 2003
Cross-reactive and specific monoclonal antibodies against cellobiohydrolases I and II and endoglucanases I and II of Trichoderma reesei journal April 1990
Determination of cell-wall porosity by microscopy: walls of cultured cells and pollen tubes journal June 1993
Studies on Starch Granules Digestion by α‐Amylase journal January 1992
Crystalline cellulose degradation: new insight into the function of cellobiohydrolases journal May 1997
Catalyst Transport in Corn Stover Internodes Elucidating Transport Mechanisms Using Direct Blue-I journal January 2006
BSA treatment to enhance enzymatic hydrolysis of cellulose in lignin containing substrates journal January 2006

Similar Records

Related Subjects

BASIC BIOLOGICAL SCIENCES
BIOMASS FUELS
AGRICULTURAL WASTES
ANTIBODIES
BIOMASS
CELL WALL
CELLULASE
CELLULOSE
ENZYMES
HYPOTHESIS
LIGNIN
MAIZE
MICROSCOPY
PLANT CELLS
STEM CELLS
SULFURIC ACID
THICKNESS
TRANSMISSION ELECTRON MICROSCOPY
TRICHODERMA VIRIDE
XYLANS
cellulase
Cel7A
biomass
corn stover
electron microscopy
lignocellulose