Response relationships between abrupt seasonal temperature changes/warming (cooling) hiatuses in China and their influencing factors.

The mechanisms of abrupt seasonal temperature changes and warming (cooling) hiatuses remain unclear. Clarifying how they respond to various influencing factors is critically important to understanding their mechanisms. In this study, the influencing factors to which the abrupt changes in Tav, Tnav, and Txav were most sensitive followed the order of (AGG and CO2) > SR > WS > AMO > PDO > MEI > AO > AP > RH. Seasonal Tav had the greatest sensitivity to all influencing factors, followed by seasonal Tav and lastly by seasonal Txav. An abrupt temperature change occurred when AGG, AMO, or SR increased continuously to a certain value, when PDO was in a positive phase (warm phase) and increased continuously to a certain value, when MEI changed abruptly, when WS and RH continued to decline for a certain time and reached a certain tendency rate, or when AP continued to decline for a certain time and reached a certain value. During the period before and after the warming (cooling) hiatuses, the temperature at most of the stations only had a significant relationship with a few influencing factors, and the hiatuses in seasonal Tav, Tnav, and Txav were overall most sensitive to changes in WS, followed by changes in RH and lastly by changes in AP. The occurrence of warming (cooling) hiatuses was highly consistent with the variation trend of some influencing factors, which to some extent affected the warming (cooling) hiatuses. Abrupt seasonal temperature changes/warming (cooling) hiatuses are the combined effects of multiple influencing factors.

Integrating a Resilience Scorecard and Landscape Performance into a Geodesign Process.

Uncertainty about the impacts of sea level rise make the ability to forecast future spatial conditions a necessary planning/design tool. Geodesign integrates multiple fields of science with change/impact models and planning/design strategies. Proactive planning analyses such as newly developed scorecards allow for plan evaluation; design strategies can now be quantitatively assessed using landscape performance calculators. Neither have been explored as Geodesign tools. A Geodesign process was developed using the resilience scorecard to assess flood vulnerability using projections for the 100 year floodplain with sea level rise by 2100. Projections were used as a guide to develop a resilient master plan for League City, TX, USA. Future impacts of the plan are projected using landscape performance measures.

Regulation of antimonite oxidation and resistance by the phosphate regulator PhoB in Agrobacterium tumefaciens GW4.

Microbial oxidation of antimonite [Sb(III)] to antimonate [Sb(V)] is a detoxification process which contributes to Sb(III) resistance. Antimonite oxidase AnoA is essential for Sb(III) oxidation, however, the regulation mechanism is still unknown. Recently, we found that the expressions of phosphate transporters were induced by Sb(III) using proteomics analysis in Agrobacterium tumefaciens GW4, thus, we predicted that the phosphate regulator PhoB may regulate bacterial Sb(III) oxidation and resistance. In this study, comprehensive analyses were performed and the results showed that (1) Genomic analysis revealed two phoB (named as phoB1 and phoB2) and one phoR gene in strain GW4; (2) Reporter gene assay showed that both phoB1 and phoB2 were induced in low phosphate condition (50 µM), but only phoB2 was induced by Sb(III); (3) Genes knock-out/complementation, Sb(III) oxidation and Sb(III) resistance tests showed that deletion of phoB2 significantly inhibited the expression of anoA and decreased bacterial Sb(III) oxidation efficiency and Sb(III) resistant. In contrast, deletion of phoB1 did not obviously affect anoA's expression level and Sb(III) oxidation/resistance; (4) A putative Pho motif was predicted in several A. tumefaciens strains and electrophoretic mobility shift assay (EMSA) showed that PhoB2 could bind with the promoter sequence of anoA; (5) Site-directed mutagenesis and short fragment EMSA revealed the exact DNA binding sequence for the protein-DNA interaction. These results showed that PhoB2 positively regulates Sb(III) oxidation and PhoB2 is also associated with Sb(III) resistance. Such regulation mechanism may provide a great contribution for bacterial survival in the environment with Sb and for bioremediation application.

Genetics and proteomics analyses reveal the roles of PhoB1 and PhoB2 regulators in bacterial responses to arsenite and phosphate.

In bacteria, phosphate (Pi) stress response is governed by the two-component regulatory system, sensor kinase PhoR and its cognate response regulatory protein PhoB. The arsenite [As(III)]-oxidizing bacterium Agrobacterium tumefaciens GW4 contains two phoB genes, phoB1 and phoB2. phoB1 is adjacent to As(III)-oxidizing genes, however, the functions of PhoB1 and PhoB2 remain unclear. Here, phoB1 and phoB2 were each deleted in-frame, and proteomics, qRT-PCR and protein-DNA interaction were performed. We found that (1) phoB1 and phoB2 were both upregulated under low Pi conditions and phoB1 was induced by As(III), but phoB2 was not; (2) deletion of phoB1 reduced As(III)-oxidizing efficiency and protein-DNA interaction analysis showed PhoB1 could interact with aioXSR promoter to regulate As(III) oxidation; (3) deletions of phoB1 or phoB2 both reduced exopolysaccharides (EPS) synthesis; and (4) PhoB1 influenced Pi uptake, As(III) oxidation, EPS synthesis, TCA cycle, energy production and stress response with As(III), and PhoB2 was associated with Pi uptake and EPS synthesis in low Pi conditions. These results showed PhoB1 and PhoB2 were both involved in Pi acquisition, PhoB1 was more important with As(III) and PhoB2 played a major role without As(III). Strain GW4 uses these two regulators to survive under low Pi and arsenic-rich environments.

Sphingosinicella humi sp. nov., isolated from arsenic-contaminated farmland soil and emended description of the genus Sphingosinicella.

A Gram-stain-negative, strictly aerobic bacterium, designated strain QZX222T, was isolated from arsenic-contaminated farmland soil. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain QZX222T was clustered with Sphingosinicella vermicomposti YC7378T (97.0 %), Sphingosinicellaxenopeptidilytica 3-2W4T (96.1 %), Sphingosinicella microcystinivorans Y2T (96.0 %) and Sphingosinicella soli KSL-125T (95.9 %). Compared to strain QZX222T, Spingomonas olgophenolica JCM 12082T and Sphingobium boeckii 469T had 16S rRNA gene similarities of 96.2 and 95.9 %, respectively, but they located in other phylogenetic clusters. DNA-DNA hybridization and genomic ANI values between strain QZX222T and Sphingosinicella vermicomposti DSM 21593T (KCTC 22446T) were 34.8 and 75.0 %, respectively. The genome size of strain QZX222T was 3.0 Mb including 2982 predicted genes. The strain had a DNA G+C content of 65.9 mol%. Strain QZX222T had ubiquinone Q-10 as the major respiratory quinone and homospermidine as the major polyamine. The major fatty acids (>10 %) of strain QZX222T were C17 : 1ω6c, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C17 : 1ω8c. The polar lipids were sphingoglycolipid, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylcholine and an unidentified glycolipid. Strain QZX222T could be distinguished from other Sphingosinicella strains based on the results of phylogenetic and genomic analyses, DNA-DNA hybridization, white colour colony, hydrolysis of urea, alkaline phosphatase activity, lack of phosphatidylmonomethylethanolamine, and presence of phosphatidylcholine. Therefore, strain QZX222T represents a novel species of Sphingosinicella, for which the name Sphingosinicellahumi sp. nov. is proposed. The type strain is QZX222T (=KCTC 62519T=CCTCC AB 2018030T).

Climate Change Armor.

Climate Change Armor is a collection of adaptive flood attenuation mechanisms for protecting newly designed communities from flood events and the eventual impacts of sea level rise. League City, TX is used as an application site. NOAA predicts that sea levels will increase and storm surge will become more frequent along the Texas coast. In the Gulf Coast, sea level projects to rise up to 629 feet by 2100. The Climate Change Armor Toolkit comprises both structural and non-structural mechanisms which are either engineered to block and control heavy floods or rely on natural systems and green infrastructure to attenuate flood waters from frequent storms or hazard flood events. With the application of the Armor Toolkit, 221,921 cubic feet of runoff can be captured, nearly 2,400 new residents are protected, over 3,000 jobs are created, $23 million in physical flood damage can be avoided, and approximately $1.3 billion can be generated in the life cycle benefits of the newly designed community by 2100.

Edaphobaculum flavum gen. nov., sp. nov., a member of family Chitinophagaceae, isolated from grassland soil.

A yellow-coloured, Gram-stain-negative, non-motile, rod-shaped, strictly aerobic bacterium, designated 1-116T, was isolated from Erdos grassland soil of Inner Mongolia, PR China. Phylogenetic analysis based on 16S rRNA genes showed that strain 1-116T was a member of family Chitinophagaceae and exhibited the highest similarities to Taibaiella koreensis THG-DT86T (90.1 %) and Flavihumibacter solisivae 3-3T (90.0 %), while the similarities to the other Chitinophagaceae type strains were lower than 90.0 %. Strain 1-116T grew at 16-33 °C (optimum 28 °C), pH 6.0-9.0 (optimum 7.0-8.0) and 0-0.5 % NaCl (w/v; optimum without NaCl). A flexirubin-type pigment was present. The DNA G+C content was 43.2 mol% and the only quinone present was menaquinone-7. The only polyamine detected was sym-homospermidine [30.7 µmol (g dry weight)-1] and the predominant fatty acids were iso-C15 : 0 (20.8 %), iso-C15 : 1 G (25.1 %), summed feature 4 (anteiso-C17 : 1 B and/or iso-C17 : 1 I; 13.8 %) and iso-C17 : 0 3-OH (13.2 %). The major polar lipids were phosphatidylethanolamine, three unidentified lipids, an unidentified aminophospholipid and an unidentified glycolipid. On the basis of the polyphasic analyses, strain 1-116T represents a novel genus and species in the family Chitinophagaceae, for which the name Edaphobaculum flavum gen. nov., sp. nov., is proposed. The type strain of Edaphobaculum flavum is 1-116T (=CCTCC AB 2017054=KCTC 52843).

Arsenite oxidation regulator AioR regulates bacterial chemotaxis towards arsenite in Agrobacterium tumefaciens GW4.

Some arsenite [As(III)]-oxidizing bacteria exhibit positive chemotaxis towards As(III), however, the related As(III) chemoreceptor and regulatory mechanism remain unknown. The As(III)-oxidizing bacterium Agrobacterium tumefaciens GW4 displays positive chemotaxis towards 0.5-2 mM As(III). Genomic analyses revealed a putative chemoreceptor-encoding gene, mcp, located in the arsenic gene island and having a predicted promoter binding site for the As(III) oxidation regulator AioR. Expression of mcp and other chemotaxis related genes (cheA, cheY2 and fliG) was inducible by As(III), but not in the aioR mutant. Using capillary assays and intrinsic tryptophan fluorescence spectra analysis, Mcp was confirmed to be responsible for chemotaxis towards As(III) and to bind As(III) (but not As(V) nor phosphate) as part of the sensing mechanism. A bacterial one-hybrid system technique and electrophoretic mobility shift assays showed that AioR interacts with the mcp regulatory region in vivo and in vitro, and the precise AioR binding site was confirmed using DNase I foot-printing. Taken together, these results indicate that this Mcp is responsible for the chemotactic response towards As(III) and is regulated by AioR. Additionally, disrupting the mcp gene affected bacterial As(III) oxidation and growth, inferring that Mcp may exert some sort of functional connection between As(III) oxidation and As(III) chemotaxis.

Mucilaginibacter pedocola sp. nov., isolated from a heavy-metal-contaminated paddy field.

Strain TBZ30T was isolated from soil of a heavy-metal-contaminated paddy field. Cells of strain TBZ30T were Gram-staining-negative, rod-shaped, non-motile and non-spore-forming. The isolate was strictly aerobic, pink-pigmented, catalase- and oxidase-positive and produced exopolysaccharides. On the basis of 16S rRNA gene phylogeny, strain TBZ30T belonged to the genus Mucilaginibacter and appeared most closely related to Mucilaginibacter gynuensis YC7003T (95.8 %), Mucilaginibacter litoreus BR-18T (95.4 %) and Mucilaginibacter mallensis MP1X4T (95.4 %). Strain TBZ30T contained menaquinone-7 as the only ubiquinone. The main cellular fatty acids included summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), iso-C15 : 0, C16 : 0, iso-C17 : 0 3-OH and C16 : 1ω5c. The polar lipids were phosphatidylethanolamine, an unidentified phospholipid, two unidentified aminophospholipids, four unidentified aminolipids, three unidentified lipids and two unidentified glycolipids. The genomic DNA G+C content was 49.0 mol%. On the basis of polyphasic taxonomy analyses, strain TBZ30T represents a novel species of the genus Mucilaginibacter, for which the name Mucilaginibacter pedocola sp. nov. is proposed. The type strain is TBZ30T (=KCTC 42833T=CCTCC AB 2015301T).