Metabolic pathway analysis of the biodegradation of cellulose by Bacillus velezensis

A green strategy that using <i>Bacillus velezensis</i> to degrade cellulose in bamboo forest waste was demonstrated. The cultivation conditions of microorganism, identified as <i>Bacillus velezensis</i> by 16S rDNA, were optimized by response surface methodology (RSM). Results showed that with a temperature of 35 °C, a pH of 6 in a Luria-Bertani (LB) medium, and a rotation speed of 140 r/min, the bamboo forest waste powder was added to the purified bacteria at a dose of 1 % (w/v), the cellulose degradation rate reached the highest value of 33.12 %. Besides, the fourier-transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and liquid chromatography-mass spectrometry (LC-MS) indicated that cellulose could be effectively degraded, with possible products including cellobiose, uridine diphosphate (UDP)-glucose, D-glucuronic acid, <i>etc</i>. The metabolic pathways involved in cellulose degradation by this strain include the pentose phosphate, starch, sucrose, and glucuronic acid pathways.