title: Metaproteomic analysis of ratoon sugarcane rhizospheric soil.
abstract: BACKGROUND
  The current study was undertaken to elucidate the mechanism of yield decline in ratoon sugarcane using soil metaproteomics combined with community level physiological profiles (CLPP) analysis.
  
  
  RESULTS
  The available stalk number, stalk diameter, single stalk weight and theoretical yield of ratoon cane (RS) were found to be significantly lower than those of plant cane (NS). The activities of several carbon, nitrogen and phosphorus processing enzymes, including invertase, peroxidase, urease and phosphomonoesterase were found to be significantly lower in RS soil than in NS soil. BIOLOG analysis indicated a significant decline in average well-color development (AWCD), Shannon's diversity and evenness indices in RS soil as compared to NS soil. To profile the rhizospheric metaproteome, 109 soil protein spots with high resolution and repeatability were successfully identified. These proteins were found to be involved in carbohydrate/energy, amino acid, protein, nucleotide, auxin and secondary metabolisms, membrane transport, signal transduction and resistance, etc. Comparative metaproteomics analysis revealed that 38 proteins were differentially expressed in the RS soil as compared to the control soil or NS soil. Among these, most of the plant proteins related to carbohydrate and amino acid metabolism and stress response were up-regulated in RS soil. Furthermore, several microbial proteins related to membrane transport and signal transduction were up-regulated in RS soil. These proteins were speculated to function in root colonization by microbes.
  
  
  CONCLUSIONS
  Our experiments revealed that sugarcane ratooning practice induced significant changes in the soil enzyme activities, the catabolic diversity of microbial community, and the expression level of soil proteins. They influenced the biochemical processes in the rhizosphere ecosystem and mediated the interactions between plants and soil microbes.
authors.affiliation: Key Laboratory of Biopesticide and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, P R China. lwx@fjau.edu.cn
authors.forename: Wenxiong
authors.initials: W
authors.lastname: Lin
authors.forename: Linkun
authors.initials: L
authors.lastname: Wu
authors.forename: Sheng
authors.initials: S
authors.lastname: Lin
authors.forename: Aijia
authors.initials: A
authors.lastname: Zhang
authors.forename: Mingming
authors.initials: M
authors.lastname: Zhou
authors.forename: Rui
authors.initials: R
authors.lastname: Lin
authors.forename: Haibin
authors.initials: H
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Zhixing
authors.initials: Z
authors.lastname: Zhang
authors.forename: Ruiyu
authors.initials: R
authors.lastname: Lin
mesh_terms: D015180:Electrophoresis, Gel, Two-Dimensional; D020543:Proteome / Q000032:analysis*; D040901:Proteomics / Q000379:methods; D058441:Rhizosphere; D031786:Saccharum / Q000254:growth & development*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D020543:Proteome; D012987:Soil