BackgroundSalvia splendens Ker-Gawl, most commonly used in China to add a splash of brilliant color to the surroundings during the warm season, is subject to heat stress, which can greatly affect its growth and yield.ResultsTo gain a comprehensive understanding of heat-tolerance mechanisms of S. splendens, we assessed the heat-stress responses and characterized the proteomes of leaves from two varieties, Vista (heat resistant) and King (heat sensitive). Denaturing two-dimensional gel electrophoresis (2–DE) and tandem mass spectrometry were used to identify heat-responsive proteins. Heat stress induced the reversible inactivation of photosystem II reaction centers and increased the amounts of antioxidative enzymes, thereby decreasing oxidative damage. Vista leaves had a much greater ability than King leaves to develop light-protective and oxygen-scavenging systems in response to heat stress. More than 1213 leaf proteome spots were reproducibly detected in the gels, with a total of 33 proteins in each leaf type differentially regulated when Salvia splendens were heat stress treated. Of these proteins, 23 and 28 from Vista and King, respectively, were identified.ConclusionsMost of the identified proteins are involved in photosynthesis, metabolism, protein processing, or stress response, indicating that many different processes work together to establish a new cellular homeostasis in response to heat stress.

The precursor of vitamin C, 2-keto-L-gulonic acid (2-KLG), is bio-converted from L-sorbose by a microbial consortium of Ketogulonicigenium vulgare and a helper strain (Bacillus spp.). Most helper strains produce siderophores. To understand the effects of siderophores on promoting 2-KLG yield, the siderophores of Bacillus pumilus SY-A9 were purified and added to a monoculture fermentation system of K. vulgare 25B-1. The results revealed that the titer of 2-KLG reached 7.18 g/L within 60 h and increased by 71.45% when the added concentration of siderophores was 500 µg/L. Moreover, the increased production of 2-KLG was accompanied by the overexpressed iron uptake system-related genes, electron transfer chain-related genes, ATP synthesis enzyme-related genes, antioxidant enzyme-related genes, and 2-KLG producing enzyme-related genes, which reduced oxidative stress and ensured the normal energy metabolism of K. vulgare 25B-1. This study demonstrated that siderophores of the helper strain play a key role in the enhancement of 2-KLG biosynthesis.

In this paper, the water quality of the Xixi Wetland was evaluated and the characteristics of water pollution were described according to the survey data. Based on the status of water quality and its functional requirements as an urban wetland, biological-ecological countermeasures were suggested. The experimental use of ecological technologies, such as artificial wetlands, ecological aquiculture and artificial floating island, were done in several fish ponds in the Xixi Wetland. Water monitoring results show that the quality of the treated water has improved significantly and the measures to purify the eutrophic water in the wetland have been effective.

No abstract

The technique of SYBR Green-based quantitative real-time reverse transcription polymerase chain reaction (real-time RT-PCR) was applied to quantitative detect a 764 bp nucleotide sequence containing total coat protein (cp) gene of Cymbidium mosaic virus (CyMV). The plasmid containing the target sequence was constructed to prepare the standard curve and detect the sensitivity. The standard curve was drawn based on the linear relationship between the logarithm (base 10) of the quantity of target sequence and cycle threshold [C(T)]. While the concentration of plasmid DNA falling within the range of 2.6Â10 7 to 2.6Â10 2 copies per tube established a regression equation, y = -0.3583x + 10.32, and related coefficient: r 2 = 0.995. The real-time RT-PCR assay for CyMV had a minimum detectable quantity of two copies per tube. The naturally infected samples of Phalaenopsis sp. and the artificially inoculated samples of Arachnis sp. with trace CyMV were quantitatively detected using this method. CyMV in the positive samples of Phalaenopsis sp. and Arachnis sp. was confirmed by DNA sequencing and cp gene homeology blast. The results showed that CyMV extracted from the leaves of orchid in Hangzhou, Zhejiang Province, China, could be derived from Kunming city (KM), Yunnan Province, China. This method characterized by high sensitivity, specificity, and precision is suitable for early diagnosis and quantitative detection of CyMV.