Jeotgalibacillus haloalkalitolerans sp. nov., a novel alkalitolerant and halotolerant bacterium, isolated from the confluence of the Fenhe River and the Yellow River.

A Gram-stain positive, aerobic, alkalitolerant and halotolerant bacterium, designated HH7-29 T, was isolated from the confluence of the Fenhe River and the Yellow River in Shanxi Province, PR China. Growth occurred at pH 6.0-12.0 (optimum, pH 8.0-8.5) and 15-40℃ (optimum, 32℃) with 0.5-24% NaCl (optimum, 2-9%). The predominant fatty acids (> 10.0%) were iso-C15:0 and anteiso-C15:0. The major menaquinones were MK-7 and MK-8. The polar lipids were phosphatidylglycerol, diphosphatidylglycerol and two unidentified phospholipids. Phylogenetic analyses based on the 16S rRNA gene sequence revealed that strain HH7-29 T was a member of the genus Jeotgalibacillus, exhibiting high sequence similarity to the 16S rRNA gene sequences of Jeotgalibacillus alkaliphilus JC303T (98.4%), Jeotgalibacillus salarius ASL-1 T (98.1%) and Jeotgalibacillus alimentarius YKJ-13 T (98.1%). The genomic DNA G + C content was 43.0%. Gene annotation showed that strain HH7-29 T had lower protein isoelectric points (pIs) and possessed genes related to ion transport and organic osmoprotectant uptake, implying its potential tolerance to salt and alkali. The average nucleotide identity, digital DNA-DNA hybridization values, amino acid identity values, and percentage of conserved proteins values between strain HH7-29 T and its related species were 71.1-83.8%, 19.5-27.4%, 66.5-88.4% and 59.8-76.6%, respectively. Based on the analyses of phenotypic, chemotaxonomic, phylogenetic and genomic features, strain HH7-29 T represents a novel species of the genus Jeotgalibacillus, for which the name Jeotgalibacillus haloalkalitolerans sp. nov. is proposed. The type strain is HH7-29 T (= KCTC 43417 T = MCCC 1K07541T).

[Self-assembly of dual-functionalized gold nanoparticle probe and its specificity].

OBJECTIVE: To investigate the specificity of the dual-functionalized nanoparticles probes (NPs) self-assembled with colloidal gold. METHODS: 13-nm gold nanoparticles were prepared with citrate reduction of HAuCl(4). These gold nanoparticles were sequentially functionalized with the specific single-strand oligonucleotide of HA gene of influenza A virus (H1N1) and disulfide molecules of m/z at 693. The NPs solution showed the red formation. The magnetic microparticles (MPs) were modified with another specific single-strand oligonucleotide in HA gene of H1N1. The sandwich complexes (MP-Target-NPs) were formed by the target DNA with the MPs and the NPs. The color change in the solution was observed and the dehybridization product was detected by MALDI TOF MS. Moreover specificity of the probes was investigated with nano-water (as a blank control) and the different target DNAs including complementary DNA,non-complementary DNA and two DNAs of one base mismatch, respectively. RESULT: The red formation and the positive signal in MS detection of reporter mass code 693 ([M+Na](+)) were observed,which indicated the formation of sandwich complexes formed only when the completely complementary target DNAs were presented in the solution. No color formation changes and no peak signal detected by MALDI TOF MS were observed,showing that none of target of interest (nano-pure water),non-complementary DNA and two DNAs of one base mismatch existed in the systems,which indicated no sandwich complexes formed between the target DNAs and the two probes. CONCLUSION: Considering the simple preparation procedure and high specificity,the dual-functionalized gold nanoparticle probes would be widely and increasingly used in nucleic acid analysis. In particular,it would have broad application prospects in early diagnosis of diseases,single nucleotide polymorphism (SNP) typing and so on.