Abstract:
 Abstract: 【Aim】 To understand the bacteria species in the watery saliva of adults of the tea green leafhopper, Empoasca flavescens, by identifying the bacterial proteins in their saliva. 【Methods】 Saliva of tea green leafhopper adults was collected by the self-made collection device with treching two layers of Parafilm with sucrose diet. After concentration by ultrafiltration and electrophoretic separation, saliva protein solution was hydrolysated by filter-aided sample preparation (FASP) method. Saliva proteins were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). The bacterial proteins in saliva were searched against the UniProt database of bacterial protein by using Mascot 2.2. 【Results】 One hundred and forty-two proteins from 49 species of bacteria in 27 orders were identified. Bacterial proteins of Proteobacteria were the most abundant, with a total of 107 proteins, among which bacterial proteins of α-Proteobacteria and γ-Proteobacteria accounted for the most. Bacterial proteins of Firmicutes (28 proteins) were the second most abundant, belonging to Bacilli and Clostrida, respectively. These proteins are involved in amino acid, vitamin and energy metabolism. 【Conclusion】 The identified bacterial proteins may be important participants in the life cycle of leafhoppers. This study provides basic information for further study on the relationship among endosymbiotic bacteria, tea green leafhoppers and tea plants.

Key words: Empoasca flavescens, saliva, bacterial protein, endosymbiotic bacteria, LC-MS/MS