Inoculation with endophytic Bacillus megaterium 1Y31 increases Mn accumulation and induces the growth and energy metabolism-related differentially-expressed proteome in Mn hyperaccumulator hybrid pennisetum

• Published in: Journal of hazardous materials Vol. 300; pp. 513 - 521
• Main Authors: Zhang, Wen-hui, He, Lin-yan, Wang, Qi, Sheng, Xia-fang
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 30.12.2015
• Subjects: Bacillus megaterium; Bacillus megaterium - metabolism; Bacillus megaterium 1Y31; Differentially-expressed proteins; Energy Metabolism - drug effects; Environmental Restoration and Remediation; Hydroponics; Manganese - metabolism; Mn accumulation; Mn hyperaccumulator hybrid pennisetum; Pennisetum; Pennisetum - growth & development; Pennisetum - metabolism; Pennisetum - microbiology; Photosynthesis - drug effects; Plant growth-promoting endophytic bacteria (PGPEB); Plant Leaves - drug effects; Plant Leaves - metabolism; Plant Proteins - biosynthesis; Plant Proteins - genetics; Plant Roots - metabolism; Proteome - drug effects; Soil Pollutants - metabolism; Mn accumulation; Differentially-expressed proteins; Mn hyperaccumulator hybrid pennisetum; Bacillus megaterium 1Y31; Plant growth-promoting endophytic bacteria (PGPEB)
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2015.07.049

•Hybrid pennisetum was a Mn hyperaccumulator.•Strain 1Y31 increased the growth and total Mn uptake of hybrid pennisetum.•The proportion of PGPEB was higher in the bacteria-inoculated plants under Mn stress.•Strain 1Y31 promoted the photosynthesis and energy metabolism of the plants. In this study, a hydroponic culture experiment was conducted in a greenhouse to investigate the molecular and microbial mechanisms involved in the endophytic Bacillus megaterium 1Y31-enhanced Mn tolerance and accumulation in Mn hyperaccumulator hybrid pennisetum. Strain 1Y31 significantly increased the dry weights (ranging from 28% to 94%) and total Mn uptake (ranging from 23% to 112%) of hybrid pennisetum treated with 0, 2, and 10mM Mn compared to the control. Total 98 leaf differentially expressed proteins were identified between the live and dead bacterial inoculated hybrid pennisetum. The major leaf differentially expressed proteins were involved in energy generation, photosynthesis, response to stimulus, metabolisms, and unknown function. Furthermore, most of the energy generation and photosynthesis-related proteins were up-regulated, whereas most of the response to stimulus and metabolism-related proteins were down-regulated under Mn stress. Notably, the proportion of indole-3-acetic acid (IAA)-producing endophytic bacteria was significantly higher in the bacterial inoculated plants under Mn stress. The results suggested that strain 1Y31 increased the growth and Mn uptake of hybrid pennisetum through increasing the efficiency of photosynthesis and energy metabolism as well as the proportion of plant growth-promoting endophytic bacteria in the plants.