title: Tetramethylammonium hydroxide (TMAH) thermochemolysis for probing in situ softwood lignin modification in each gut segment of the termite.
abstract: Termites are highly effective in lignocellulose degradation; however, the process of lignin deconstruction along the alimentary canal is not well understood. In this study, the wood metabolites in each gut segment were tentatively analyzed using pyrolysis-gas chromatography-mass spectrometry in the presence of tetramethylammonium hydroxide. Collectively, the significant differences in the pyrolysate distribution among each sample established (1) conservation of the major β-O-4' bonds of lignin during termite digestion, although a selective lignin substructure modification was observed across the whole gut; (2) initiation of lignin-polysaccharide dissociation, aliphatic oxidation/carboxylation, phenolic dehydroxylation in the foregut, and linkage modification of the 5-5', β-5', and β-1' substructures; (3) the continuation of foregut reactions into the midgut with further phenolic carboxylation/demethoxylation/carbonylation; and (4) phenolic/aliphatic esterifications in the hindgut. Overall, elucidation of the stepwise lignin unlocking mechanism in termites provides a valuable insight for understanding plant cell wall structure and its recalcitrance.
authors: Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164-6120, USA.
authors: Jing
authors: J
authors: Ke
authors: Dhrubojyoti D
authors: DD
authors: Laskar
authors: Shulin
authors: S
authors: Chen
mesh_terms: D000818:Animals; D004063:Digestion; D041981:Gastrointestinal Tract / Q000378:metabolism*; D020049:Isoptera / Q000737:chemistry / Q000378:metabolism*; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D014934:Wood / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000644:Quaternary Ammonium Compounds; D008031:Lignin; C027917:tetramethylammonium