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A facultatively chemolithoautotrophic, thiosulfate-oxidizing, Gram-negative, aerobic, motile, rodshaped bacterial strain, designated ATSB16 T , was isolated from rhizosphere soils of sesame (Sesamum indicum L.). 16S rRNA gene sequence analysis demonstrated that this strain was closely related to Pandoraea pnomenusa LMG 18087 T (96.7 % similarity), P. pulmonicola LMG 18016 T (96.5 %), P. apista LMG 16407 T (96.2 %), P. norimbergensis LMG 18379 T (96.1 %) and P. sputorum LMG 18819 T (96.0 %). Strain ATSB16 T shared 96.0-96.4 % sequence similarity with four unnamed genomospecies of Pandoraea. The major cellular fatty acids of the strain ATSB16 T were C 17 : 0 cyclo (33.0 %) and C 16 : 0 (30.6 %). Q-8 was the predominant respiratory quinone. The major polar lipids were phosphatidylmethylethanolamine, diphosphatidylglycerol, phosphatidylethanolamine and two unidentified aminophospholipids. Hydroxyputrescine and putrescine were the predominant polyamines. The genomic DNA G+C content of the strain was 64.0 mol%. On the basis of the results obtained from this study, strain ATSB16 T represents a novel species of the genus Pandoraea, for which the name Pandoraea thiooxydans sp. nov. is proposed. The type strain is ATSB16 T (5KACC 12757 T 5LMG 24779 T ).Currently, the genus Pandoraea consists of five species, namely Pandoraea pnomenusa, P. pulmonicola, P. apista, P. norimbergensis and P. sputorum, and four genomospecies (Coenye et al., 2000;Daneshvar et al., 2001). During a study of thiosulfate-oxidizing bacterial populations in sesame rhizosphere soils, one of the isolates, strain ATSB16 T , was subjected to phenotypic, genotypic and chemotaxonomic investigations in order to determine its taxonomic position.Rhizosphere soil samples were collected from sesame (Sesamum indicum L.) cultivated in fields in Jung ha-dong (35 u 10-179 N 128 u 49-569 E), Republic of Korea.Rhizosphere soil (soil still attached to the roots after gentle shaking) and fine roots (approximately 1 cm in length) from five plants were pooled into one sample, homogenized by thorough hand-mixing and used for enrichment isolation. Each rhizosphere soil sample (10 g) was added to 100 ml liquid mineral salts thiosulfate (MST) medium (Mukhopadhyaya et al., 2000) and incubated in a rotary shaker at 30 u C, in the dark to avoid any growth of phototrophic bacteria, until the colour of the indicator in the medium, bromcresol purple, changed to yellow. To isolate pure cultures, 10-fold dilutions (10 2 -10 6 ) were made with sterile deionized water and 0.2 ml aliquots were spread with sterile glass sticks on MST agar. Colonies that developed a yellow halo against a purple background, indicative of the production of sulfuric acid resulting fromThe GenBank/EMBL/DDBJ accession number for the 16S rRNA gene sequence of strain ATSB16 T is EF397578.

The bacteria B1-9 that was isolated from the rhizosphere of the green onion could promote growth of pepper, cucumber, tomato, and melon plants. In particular, pepper yield after B1-9 treatment on the seedling was increased about 3 times higher than that of control plants in a field experiment. Partial 16S rDNA sequences revealed that B1-9 belongs to the genus Pantoea ananatis. Pathogenecity tests showed non-pathogenic on kimchi cabbage, carrot, and onion. The functional characterization study demonstrated B1-9's ability to function in phosphate solubilization, sulfur oxidation, nitrogen fixation, and indole-3-acetic acid production. To trace colonization patterns of B1-9 in pepper plant tissues, we used DRAQ5™ fluorescent dye, which stains the DNAs of bacteria and plant cells. A large number of B1-9 cells were found on the surfaces of roots and stems as well as in guard cells. Furthermore, several colonized B1-9 cells resided in inner cortical plant cells. Treatment of rhizosphere regions with strain B1-9 can result in efficient colonization of plants and promote plant growth from the seedling to mature plant stage. In summary, strain B1-9 can be successfully applied in the pepper plantation because of its high colonization capacity in plant tissues, as well as properties that promote efficient plant growth.