Two phosphate-and potassium-solubilizing strains (KNP413 and KNP414) were isolated from the soil of Tianmu Mountain, Zhejiang Province (China) and they were phenotypically and phylogenetically characterized. Both isolates effectively dissolved mineral phosphate and potassium, while strain KNP414 showed higher dissolution capacity even than Bacillus mucilaginosus AS1.153, the inoculant of potassium fertilizer widely used in China. When grown on Aleksandrov medium, both strains were rod-shaped spore-formers with a large capsule, and they formed slimy and translucent colonies. The DNA G+C contents were 57.7 mol% for strain KNP413 and 56.1 mol% for strain KNP414. Strain KNP413 shared a 16S rRNA gene sequence similarity of more than 99.1% with strain KNP414 and Bacillus mucilaginosus strains HSCC 1605 and YNUC0001, and a 94.6% similarity with Bacillus mucilaginosus VKM B-1480D, the type strain of Bacillus mucilaginosus. Strains KNP413 and KNP414 together with other Bacillus mucilaginosus were clustered with Paenibacillus strains in a group. The use of a specific PCR primer PAEN515F designed for differentiating the genus Paenibacillus from other members of the Bacillaceae showed that strains KNP413 and KNP414 had the same amplified 16S rRNA gene fragment (0.9-kb) as members of the genus Paenibacillus. In conclusion, phosphate-and potassium-solubilizing strains KNP413 and KNP414 should be integrated into the same species different from strain VKM B-1480D and they might be transferred to the genus of Paenibacillus, i.e. Paenibacillus mucilaginosus.
Representative strains of serogroup A Neisseria meningitidis were chosen from all mawjor meningitis epidemics worldwide since 1960 and subjected to analysis for the electrophoretic variation of 15 cytoplasmic allozymes and four outer membrane proteins. The 290 strains defined 84 unique electrophoretic types which were classified in nine subgroups. Tests with monoclonal antibodies specific for conserved pilin epitopes showed that the class I, Ha, and IIb epitopes were uniform within the subgroups. Similarly, the subgroups were uniform for expression of different variable regions of class 1 outer membrane protein, with a few minor exceptions. Many of the bacteria tested were isolated in the People's Republic of China, and the epidemiology of Chinese epidemics of meningococcal meningitis is described. The analysis approaches a global description of P1.7 A'dam 1 J. Poolman (2) P1.9 W316 (IgG2a) M. Achtman (5) P1.10 MN2OF4.17 (IgG2b) J. Poolman P1.12 MN20A7.10 (IgG3) J. Poolman P1.14 MN21G3.17 (IgG3) J. Poolman P1.15 MN3C5C (IgG3) J. Poolman (2) P1.16 62D12-8 (IgG3) J. Poolman (2) P1.x V502 (IgG2a) M. Achtman (5) Pl.y
Novel specific 16S rDNA-targeted primers were successfully designed and applied to the characterization of endophytic diversity in Dendrobium officinale. Using the popular universal bacterial primers 27f/1492r, the fragments of chloroplast and mitochondrion 16S/18S rDNA were amplified from D. officinale. They shared high nucleotide identity with the chloroplast 16S rDNAs (99-100 %) and with the mitochondrion 18S rDNAs (93-100 %) from various plants, respectively, and both shared 73-86 % identities with the bacterial 16S rDNA sequences in GenBank. The current bacterial universal primers, including 27f/1492r, match well with the chloroplast and mitochondrion 16S/18S rDNAs, which accordingly renders these primers not useful for endophytic diversity analysis. Novel 16S rDNA-targeted primers fM1 (5'-CCGCGTGNRBGAHGAAGGYYYT-3') and rC5 (5'-TAATCCTGTTTGCTCC CCAC-3') were designed, which show good specificity compared to the 16S/18S rDNAs of D. officinale, and perfect universality within bacteria except for Cyanobacteria. The primers fM1/rC5, together with 515f-GC/rC5, which overlaps the whole V4 region of 16S rDNA, were subjected to nested polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) to analyze the diversity of endophytic bacteria in D. officinale from three different sources in China. The results showed diversities in roots and stems of the plants from all three locations. Altogether, 29 bands were identified as bacteria, with the dominant group being Proteobacteria and the dominant genus being Burkholderia, some of which commonly has the function of nitrogen fixation and thus may play potentially important roles in D. officinale. Therefore, the nested PCR-DGGE method based on the novel primers provides a good alternative for investigating the communities and roles of endophytes in D. officinale.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.