Cell wall proteomics of sugarcane cell suspension cultures

Abstract

The use of cell walls to produce cellulosic ethanol from sugarcane bagasse is a new challenge. A better knowledge of proteins involved in cell wall remodelling is essential to improve the saccharification processes. Cell suspension cultures were used for this first cell wall proteomics study of sugarcane. Proteins extracted from cell walls were identified using an adapted protocol. They were extracted using 0.2 M CaCl2 and 2 M LiCl after purification of cell walls. The proteins were then identified by the innovative nanoACQUITY UPLC MS/MS technology and bioinformatics using the translated SUCEST EST cluster database of sugarcane. The experiments were reproduced three times. Since Sorghum bicolor is the closest plant with a fully sequenced genome, homologous proteins were searched for to complete the annotation of proteins, that is, prediction of subcellular localization and functional domains. Altogether, 69 different proteins predicted to be secreted were identified among 377 proteins. The reproducibility of the experiments is discussed. These proteins were distributed into eight functional classes. Oxidoreductases such as peroxidases were well represented, whereas glycoside hydrolases were scarce. This work provides information about the proteins that could be manipulated through genetic transformation, to increase second-generation ethanol production.

Glycoside Hydrolases in Plant Cell Wall Proteomes: Predicting Functions That Could Be Relevant for Improving Biomass Transformation Processes

“…This distribution varies according to organ and developmental stage. In cell suspension cultures, only 4 GH families were identified among which GH3 was the most populated [28]. In 2-month-old stems, 7 GH families were found, GH3 also being the most represented [29].…”

“…In sugarcane, 49 GHs have been identified in cell wall proteomes [28,29]. They are distributed in 16 GH families.…”

“…Ten GH3s have been identified in sugarcane [28][29][30] and nine GH3s have been identified in B. distachyon [31,32,34]. Half of the sugarcane GH3 are predicted to have a β-glucosidase activity (GO:0008422) (e.g., SCEZLB1007A09, SCEQLR1093F09, and SCQSLR1089A04).…”

Cell Wall Proteomics as a Means to Identify Target Genes to Improve Second‐Generation Biofuel Production

“…In the case of sugarcane, three types of materials have been studied Figures C E : 11-dayold cell suspension cultures [62], 2-month-old stems [30], and 4-month-old young or mature leaves and apical or basal internodes [63]. The aim was to identify among CWPs possible targets for cell wall modiication in order to facilitate E2G production.…”

“…Cell walls were resuspended in these bufers and centrifuged at high speed 40,000×g/15 min/ 4°C . The four supernatants were pooled.The same DP with minor modiications was used for sugarcane cell suspension cultures and 2-month-old stems [30,62]. "nother extraction method was tested with young or mature leaves and basal or apical internodes.…”