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We reconstructed the first genome-scale metabolic network of the plant pathogen Pectobacterium carotovorum subsp. carotovorum PC1 based on its genomic sequence, annotation, and physiological data. Metabolic characteristics were analyzed using flux balance analysis (FBA), and the results were afterwards validated by phenotype microarray (PM) experiments. The reconstructed genome-scale metabolic model, iPC1209, contains 2235 reactions, 1113 metabolites and 1209 genes. We identified 19 potential bactericide targets through a comprehensive in silico gene-deletion study. Next, we performed virtual screening to identify candidate inhibitors for an important potential drug target, alkaline phosphatase, and experimentally verified that three lead compounds were able to inhibit both bacterial cell viability and the activity of alkaline phosphatase in vitro. This study illustrates a new strategy for the discovery of agricultural bactericides.

PREMISE OF THE STUDY Calocedrus is among the genera with a typical eastern Asian-western North American disjunct distribution today. The origin of its modern distribution pattern can be better understood by examining its fossil record. METHODS The present article reports for the first time a new fossil species of this genus based on compressed material from the Oligocene Ningming Formation of Guangxi, South China, in its present major distribution area in eastern Asia. KEY RESULTS Calocedrus huashanensis sp. nov. is most similar to the two extant eastern Asian species, C. macrolepis and C. formosana, in gross morphology of foliage shoots and bears a close resemblance to the latter in cuticle structure. It shows a general similarity to the North American fossil representatives of the genus in alternately branched foliage shoots but is clearly different from the European Paleogene species characterized by oppositely branched leafy shoots. CONCLUSIONS This discovery provides new evidence for the floristic exchange of this genus between eastern Asia and North America before the Oligocene (most likely in the Eocene), presumably via the Bering land bridge. The flattened leafy shoots and dimorphic leaves with thin cuticle, open stomatal pits, and shallowly sunken guard cells of the present fossils suggest a rather humid climate during the Oligocene in the Ningming area, South China.

A new soap-free water-borne coating (solid content ca. 35 wt %) has been obtained by adding the coordination-crosslinking agent M(NH3)42+ into the —COO−-containing polyacrylate hydrosol (P—COO−). The transmission electron microscope analysis has been used to investigate the coordination-crosslinking process of the polyacrylate hydrosol with Zn(NH3)42+ in the water-borne coating of low concentration (solid content ca. 0.05 wt %). The existence of the coordination-crosslinking polymer (P—COO−)nM2+) both in the water-borne coating of low concentration (solid content ca. 0.3 wt %) and in the coating film has been detected by the linear sweep voltammetry polarographic analysis, ultraviolet-visible spectrographic analysis, and IR spectrographic analysis. All the experimental results show that the polyacrylate hydrosol (P—COO−) can take the coordination-crosslinking reaction with metal ion M2+ to form the coordination polymer [(P—COO−)nM2+]. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2457–2463, 1997

The effect of the amount of triethanolamine zirconium isopropyloxide chelate in acrylate terpolymer soap-free hydrosol on the properties of hydrosol and its film was studied. The addition of the chelate increased the hydrosol viscosity to 20 mPas and improved the hydrosol film water resistance; the water uptake was reduced to 0.6%, and the hydrosol still retained good resolubility. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2858–2860, 2003