Physiological And Biochemical And Proteomics Analysis Of Gracilaria Under N,Pb,Cd Stresses

Gracilaria is an important economic red algae. It can be used to imporve the marine environment by absorbing a large number of carbon, nitrogen, phosphorus. However, some stress factors, such as be short of nitrogen, heavy metal pollution, can cause the decline of culture Gracilaria on the productivity and quality. In this study, to investigate the change of Gracilaria, the responses of physiological and biochemical and the proteins expression in different concentration of N and heavy metals were analyzed. We hope to get the preliminary insight of the mechanism of Gracilaria how to resist environment stresses on the level of proteome.The results showed that, N treatments resulted in an increase in Gracilaria tenuistipitata var.liui growth, and the increase in Gracilaria tenuistipitata var.liui reached maximum at 200μmol/L N. The soluble protein and phycoerythrin are same with it. Pb treatments resulted in a decrease in Gracilaria growth. However, the decrease in Gracilaria was significant at 5 mg/L Pb2+, and the soluble protein and phycoerythin are also same with it. The activity of SOD, POD and GST increased in low concentrations of Pb2+(≤2.5 mg/L), and then linearly decreased with increasing Pb2+ stress.For the separation and quantification of Gracilaria lemaneiformis protein, a suitable 2-DE system was developed through of different components and concentrations in isolation solutions. The results showed that, using Trizol for the extraction of proteins, can get high quality 2-DE map with the condition of 30000Vh.For further understanding the molecular mechanism of Gracilaria lemaneiformis against the Pb2+, Cd2+ and N stress, by carrying out the comparative proteomic analysis, we identified a group of new proteins, which are involved in processe in metabolism, energy production, DNA repair, gene expression proteins and detoxification, these proteins included sugar transport ATP-binding protein, ABC transporter, DNA mismatch repair protein MutL , G protein, Tripartite ATP-independent periplasmic transporter DctQ component, Glutamine synthetase, type II secretion system protein E, ATP-dependent helicase HrpA, casein kinase, excinuclease ABC.