ADVERTISEMENT
2 /3 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Biological Chemistry

Cellulose-Building Enzyme Uncloaked

Scientists solve the underlying structure of the protein supercomplex that makes plant cell walls

by Stephen K. Ritter
October 6, 2014 | APPEARED IN VOLUME 92, ISSUE 40

CELLULOSE BUILDER
[+]Enlarge
Credit: Nicholas Carpita
The catalytic region of cellulose synthase lies at the center of the protein envelope determined by small-angle X-ray scattering, flanked by smaller P-CR and CSR regions. The CSR region is proposed to be responsible for coupling two monomers into a dimer that forms the main building block for the overall cellulose-building protein complex.The catalytic region of cellulose synthase lies at the center of the protein envelope determined by small-angle X-ray scattering, flanked by smaller Plant-Conserved Regions (P-CR) and Class-specific Regions (CSR). The CSR region is proposed to be responsible for coupling two monomers into a dimer that forms the main building block for the overall cellulose-building protein complex.
09240-scicon-CENFig2_18279748-690.jpg
Credit: Nicholas Carpita
The catalytic region of cellulose synthase lies at the center of the protein envelope determined by small-angle X-ray scattering, flanked by smaller P-CR and CSR regions. The CSR region is proposed to be responsible for coupling two monomers into a dimer that forms the main building block for the overall cellulose-building protein complex.The catalytic region of cellulose synthase lies at the center of the protein envelope determined by small-angle X-ray scattering, flanked by smaller Plant-Conserved Regions (P-CR) and Class-specific Regions (CSR). The CSR region is proposed to be responsible for coupling two monomers into a dimer that forms the main building block for the overall cellulose-building protein complex.

Scientists have at last discovered the underlying framework structure of the protein supercomplex that makes cellulose, the biopolymer foundation of plant cell walls. The work led by Purdue University’s Nicholas C. Carpita provides the most detailed glimpse to date of the process by which cellulose is stitched together from glucose molecules. The findings could lead to new ways to engineer plant fibers to make better textiles and easier ways to break down biomass to make fuels and chemicals (Plant Cell 2014, DOI: 10.1105/tpc.114.126862). Cellulose is composed of several dozen strands of glucose sugars linked together in a cablelike structure and condensed into a crystal. The rigidity of cellulose allows plants to stand upright and lends wood its strength. The cellulose-producing protein complex is made of up to 36 individual cellulose synthase enzyme units, each of which synthesizes a glucose chain independently. Carpita and coworkers used small-angle X-ray scattering to show that the enzyme unit is an elongated molecule with a central catalytic domain flanked by two smaller regions. One of the smaller regions couples with a second enzyme to form a dimer. They propose that these dimers organize into larger units that form the overall protein complex.

X

Article:

This article has been sent to the following recipient:

Leave A Comment

*Required to comment