A novel GH6 cellobiohydrolase from Paenibacillus curdlanolyticus B-6 and its synergistic action on cellulose degradation

作者：Baramee Sirilak; Teeravivattanakit Thiti****; Phitsuwan Paripok; Waeonukul Rattiya; Pason Patthra; Tachaapaikoon Chakrit; Kosugi Akihiko; Sakka Kazuo; Ratanakhanokchai Khanok^*

来源：Applied Microbiology and Biotechnology, 2017, 101(3): 1175-1188.

DOI：10.1007/s00253-016-7895-8

• Cellobiohydrolase
• Cellulose degradation
• Endoglucanase
• beta-Glucosidase
• Glycoside hydrolase family 6
• Paenibacillus curdlanolyticus

We recently discovered a novel glycoside hydrolase family 6 (GH6) cellobiohydrolase from Paenibacillus curdlanolyticus B-6 (PcCel6A), which is rarely found in bacteria. This enzyme is a true exo-type cellobiohydrolase which exhibits high substrate specificity on amorphous cellulose and low substrate specificity on crystalline cellulose, while this showed no activity on substitution substrates, carboxymethyl cellulose and xylan, distinct from all other known GH6 cellobiohydrolases. Product profiles, HPLC analysis of the hydrolysis products and a schematic drawing of the substrate-binding subsites catalysing cellooligosaccharides can explain the new mode of action of this enzyme which prefers to hydrolyse cellopentaose. PcCel6A was not inhibited by glucose or cellobiose at concentrations up to 300 and 100 mM, respectively. A good synergistic effect for glucose production was found when PcCel6A acted together with processive endoglucanase Cel9R from Clostridium thermocellum and beta-glucosidase CglT from Thermoanaerobacter brockii. These properties of PcCel6A make it a suitable candidate for industrial application in the cellulose degradation process.

• 出版日期2017-2