Comparison of the PCB serum levels among mother-child pairs in areas of Eastern Japan and Central Taiwan.

Polychlorinated biphenyls (PCBs) have been prohibited for two decades in Japan and Taiwan. The aim of this study was to compare the PCB congeners in maternal and cord serum between two countries. Our study subjects were 248 and 100 mother-child pairs in Japan and Taiwan. The measured levels of 23 serum PCB congeners between two countries were analyzed using gas chromatography-electron capture negative ionization quadrupole mass spectrometry (GC-NICI-qMS). The statistical comparisons were conducted by Student's t-test and principal component analysis with further stratification by maternal age and parity. The maternal total PCBs levels in Japan (426 ± 244 pg/g wet wt) were significantly higher than those in Taiwan (254 ± 155 pg/g wet wt), and the similar results were found in cord total PCBs levels (97 ± 76 and 58 ± 87 pg/g wet wt). It showed different distributions of PCB congeners between two countries. Whether in maternal or cord serum, the CB138, CB153 and CB180 were the highest detectable congeners whether in Japan or Taiwan. And, the CB66, CB99, CB206 and CB209 were only detected in maternal serum of Taiwan. The women of advanced maternal age had higher levels of PCB congeners, especially in Taiwan, and the primiparous women had higher levels of PCB congeners in two countries. In summary, the PCB congeners in Japan's mother-child pairs were with higher levels and different distributions when compared to those in Taiwan, and the maternal age and parity were important factors associated with the PCB levels.

Association between the First Occurrence of Asthma and Residential Greenness in Children and Teenagers in Taiwan.

Green spaces have benefits but may also increase the risk of allergic disease. This study examined the association between the first occurrence of asthma and greenness exposure in children and teenagers. We conducted a 1:1 matched case-control study matched by sex, age, and the first diagnosis year with 7040 eligible subjects from a systematic sampling cohort database in Taiwan from 2001 to 2013. A normalized difference vegetation index (NDVI) value ≥0.4 was used as the criterion to determine the green space. The green cover images were then transformed to the green coverage rate in the township surrounding the residential areas of the asthma and control subjects. Conditional logistic regression analyses demonstrated that a significantly increased risk of asthma in preschool children was associated with the surrounding greenness after adjusting for urbanization level, frequency of healthcare provider visits, mean township family income, CO, NOx, and PM2.5. The risk of asthma occurrence increased significantly with increasing greenness exposure (p-trend < 0.05). Nevertheless, exposure to the highest greenness levels (81-100%) was not associated with a significantly higher risk of asthma occurrence than was exposure to the lowest values (0-20%) of greenness. This study suggests that green space design should consider more effective methods of reducing the allergy impact.

Pseudomonas taiwanensis sp. nov., isolated from soil.

A novel Gram-negative, rod-shaped, motile, non-spore-forming bacterial strain, CMS(T), isolated from soil was characterized using phenotypic and molecular taxonomic methods. 16S rRNA gene sequence analysis revealed that the organism belongs phylogenetically to the genus Pseudomonas. Pseudomonas monteilii, P. plecoglossicida and P. mosselii were the most closely related species, with 16S rRNA gene sequence similarities to the respective type strains of 99.79, 99.73 and 99.59 %. Relatively low gyrB gene sequence similarities (<90 %) and DNA-DNA reassociation values (<51 %) were obtained between the strain and its phylogenetically closest neighbours. The G+C content of strain CMS(T) was 62.7 mol%. The major cellular fatty acids were C(18 : 1) ω 7c, summed feature 3 (C(16 : 1) ω 7c and/or iso-C(15 : 0) 2-OH), C(16 : 0) and C(10 : 0) 3-OH. Based on the phenotypic and genetic evidence, the strain is suggested to represent a novel species, for which the name Pseudomonas taiwanensis sp. nov. is proposed. The type strain is CMS(T) (=BCRC 17751(T) =DSM 21245(T)).

Lactobacillus taiwanensis sp. nov., isolated from silage.

Strain FIRDI 006T, isolated from silage cattle feed, was characterized by using phenotypic and molecular taxonomic methods. The strain was a homofermentative lactic acid bacterium; the cells stained Gram-positive and were catalase-negative, non-motile, facultatively anaerobic rods. 16S rRNA gene sequence analysis revealed that the strain belongs phylogenetically to the genus Lactobacillus and can be placed within the Lactobacillus acidophilus-delbrueckii group. Lactobacillus gasseri and Lactobacillus johnsonii were the most closely related species, with 16S rRNA gene sequence similarities of 99.53 and 99.46% to the respective type strains. Low gyrB gene sequence similarities (<90%) and low DNA-DNA reassociation values (<45%) were obtained between the strain and the phylogenetically closest neighbours. Based on phenotypic and genetic evidence, the strain is considered to represent a novel species, for which the name Lactobacillus taiwanensis sp. nov. is proposed. The type strain is FIRDI 006T (=BCRC 17755T =DSM 21401T).

The beta-tubulin gene as a molecular phylogenetic marker for classification and discrimination of the Saccharomyces sensu stricto complex.

The Saccharomyces sensu stricto complex comprises seven very closely related species. In this study, we compared the use of two different phylogenetic markers, the 26S rDNA and beta-tubulin genes, for discriminating phylogenetic relationships among Saccharomyces sensu stricto strains using sequencing as well as RFLP methods. The average sequence similarity for the beta-tubulin gene (90.0%) among seven strains was significantly less than that for 26S rDNA (98.6%). This result demonstrates that beta-tubulin gene sequences provided higher resolution than 26S rDNA sequences. Species-specific restriction profiles of the Saccharomyces strains were obtained by cutting them with the Tsp509I enzyme. Our data indicate that phylogenetic relationships between these strains are best resolved using sequencing or RFLP analysis of the beta-tubulin gene.

Paenibacillus taichungensis sp. nov., from soil in Taiwan.

Among a large collection of Taiwanese soil isolates, a novel Gram-variable, rod-shaped, motile, endospore-forming bacterial strain, strain V10537(T), was subjected to a polyphasic study including 16S rRNA and gyrB gene sequence analysis, DNA-DNA hybridization experiments, cell wall peptidoglycan type, cellular fatty acid composition analysis and comparative phenotypic characterization. 16S rRNA gene sequence analysis indicated that the organism belonged to the genus Paenibacillus. Strain V10537(T) possessed meso-diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan. It contained menaquinone MK-7 as the predominant isoprenoid quinone and anteiso-C(15 : 0) (53.6 %) and C(16 : 0) (19.0 %) as the major fatty acids. Phylogenetically, the most closely related species to strain V10537(T) were Paenibacillus pabuli, Paenibacillus xylanilyticus, Paenibacillus amylolyticus, Paenibacillus barcinonensis and Paenibacillus illinoisensis, with 16S rRNA gene sequence similarities of 99.5, 98.8, 98.3, 98.2 and 98.1 % to the respective type strains. The gyrB gene sequence similarities between strain V10537(T) and these strains were 76.9-85.0 %. DNA-DNA hybridization experiments showed levels of relatedness of 8.5-45.6 % between strain V10537(T) and these strains. The DNA G+C content of strain V10537(T) was 46.7 mol%. Strain V10537(T) was clearly distinguishable from other Paenibacillus species and thus represents a novel species of the genus Paenibacillus, for which the name Paenibacillus taichungensis sp. nov. is proposed. The type strain is V10537(T) (=BCRC 17757(T) =DSM 19942(T)).

A novel specific DNA marker in Saccharomyces bayanus for species identification of the Saccharomyces sensu stricto complex.

This study was based on RAPD fingerprinting for species identification of the Saccharomyces sensu stricto complex. 40 random primers were used for RAPD analysis. The results showed that one of these primers, OPT-18, produced a 974 bp species-specific band, which was only found in the tested S. bayanus. Afterward this specific fragment was isolated from agarose gel and ligated into vector for DNA sequencing. A pair of primer SpeOPT18Sbay-F2 and SpeOPT18Sbay-R2 were designed according to the cloned species-specific sequence, which was employed for PCR with the template DNA of the S. sensu stricto strains, single 779 bp species-specific band was only found in S. bayanus. Therefore, we conclude that our novel species DNA marker could be used to rapidly and accurately identify the species of S. bayanus from S. sensu stricto complex by direct PCR.

Bacillus velezensis is a later heterotypic synonym of Bacillus amyloliquefaciens.

Strain BCRC 14193, isolated from soil, shared more than 99 % 16S rRNA gene sequence similarity with Bacillus amyloliquefaciens BCRC 11601(T) and Bacillus velezensis BCRC 17467(T). This strain was previously identified as B. amyloliquefaciens, based on DNA-DNA hybridization, but its DNA relatedness value with B. velezensis BCRC 17467(T) was 89 %. To investigate the relatedness of strain BCRC 14193, B. amyloliquefaciens and B. velezensis, the partial sequence of the gene encoding the subunit B protein of DNA gyrase (gyrB) was determined. B. velezensis BCRC 17467(T) shared high gyrB gene sequence similarity with B. amyloliquefaciens BCRC 14193 (98.4 %) and all of the B. amyloliquefaciens strains available (95.5-95.6 %). DNA-DNA hybridization experiments revealed high relatedness values between B. velezensis BCRC 17467(T) and B. amyloliquefaciens BCRC 11601(T) (74 %) and the B. amyloliquefaciens reference strains (74-89 %). Based on these data and the lack of phenotypic distinctive characteristics, we propose Bacillus velezensis as a later heterotypic synonym of Bacillus amyloliquefaciens.

Comparison of gyrB gene sequences, 16S rRNA gene sequences and DNA-DNA hybridization in the Bacillus subtilis group.

The Bacillus subtilis group comprises eight closely related species that are indistinguishable from one another by 16S rRNA gene sequence analysis. Therefore, the gyrB gene, which encodes the subunit B protein of DNA gyrase, was selected as an alternative phylogenetic marker. To determine whether gyrB gene sequence analysis could be used for phylogenetic analysis and species identification of members of the B. subtilis group, the congruence of gyrB grouping with both 16S rRNA gene sequencing and DNA-DNA hybridization data was evaluated. Ranges of gyrB nucleotide and translated amino acid sequence similarities among the eight type strains were 75.4-95.0 % and 88.5-99.2 %, respectively, whereas 16S rRNA gene sequence similarities were 98.1-99.8 %. Results showed that gyrB gene sequences provide higher resolution than 16S rRNA gene sequences. The classification achieved by gyrB sequence analysis was in agreement with results obtained with DNA-DNA hybridization. It is concluded that the gyrB gene may be an efficient alternative target for identification and taxonomic analysis of members of the B. subtilis group.

Reclassification of Bacillus axarquiensis Ruiz-Garcia et al. 2005 and Bacillus malacitensis Ruiz-Garcia et al. 2005 as later heterotypic synonyms of Bacillus mojavensis Roberts et al. 1994.

The Bacillus subtilis group encompasses the taxa Bacillus subtilis subsp. subtilis, B. licheniformis, B. amyloliquefaciens, B. atrophaeus, B. mojavensis, B. vallismortis, B. subtilis subsp. spizizenii, B. sonorensis, B. velezensis, B. axarquiensis and B. malacitensis. In this study, the taxonomic relatedness between the species B. axarquiensis, B. malacitensis and B. mojavensis was investigated. Sequence analysis of the 16S rRNA gene and the gene for DNA gyrase subunit B (gyrB) confirmed the very high similarities between these three type strains and a reference strain of B. mojavensis (>99 and >97 %, respectively). DNA-DNA hybridization experiments revealed high relatedness values between the type strains of B. axarquiensis, B. malacitensis and B. mojavensis and between these strains and a reference strain of B. mojavensis (83-98 %). Based on these molecular taxonomic data and the lack of phenotypic distinctive characteristics, Bacillus axarquiensis and Bacillus malacitensis should be reclassified as later heterotypic synonyms of Bacillus mojavensis.

Paenibacillus taiwanensis sp. nov., isolated from soil in Taiwan.

Among a large collection of Taiwanese soil isolates, a novel Gram-variable, rod-shaped, motile and endospore-forming bacterial strain, designated G-soil-2-3(T), was isolated from farmland soil in Wu-Feng, Taiwan. The isolate was subjected to a polyphasic study including 16S rRNA gene sequence analysis, DNA-DNA hybridization experiments, fatty acid analysis and comparative phenotypic characterization. 16S rRNA gene sequence analysis indicated that the organism belongs within the genus Paenibacillus. It contained menaquinone MK-7 as the predominant isoprenoid quinone and anteiso-C(15 : 0) (40.5 %), iso-C(15 : 0) (13.1 %), iso-C(16 : 0) (10.8 %) and anteiso-C(17 : 0) (7.3 %) as the major fatty acids. Phylogenetically, the closest relatives of strain G-soil-2-3(T) were the type strains of Paenibacillus assamensis, Paenibacillus alvei and Paenibacillus apiarius, with 16S rRNA gene sequence similarity of 95.7, 95 and 95.2 %, respectively. DNA-DNA hybridization experiments showed levels of relatedness of 2.8-9.0 % of strain G-soil-2-3(T) with these strains. The G+C content of the DNA was 44.6 mol%. Strain G-soil-2-3(T) was clearly distinguishable from P. assamensis, P. alvei and P. apiarius and thus represents a novel species of the genus Paenibacillus, for which the name Paenibacillus taiwanensis sp. nov. is proposed. The type strain is G-soil-2-3(T) (=BCRC 17411(T)=IAM 15414(T)=LMG 23799(T)=DSM 18679(T)).

Chryseobacterium taiwanense sp. nov., isolated from soil in Taiwan.

Among a large collection of Taiwanese soil isolates, a novel Gram-negative, rod-shaped, non-spore-forming, yellow-pigmented bacterial strain, Soil-3-27(T), was isolated from farmland soil in Wu-Feng, Taiwan. The isolate was subjected to a polyphasic study including 16S rRNA gene sequencing, DNA-DNA hybridization, fatty acid analysis and comparative phenotypic characterization. The 16S rRNA gene sequence analysis indicated that the organism belongs to the genus Chryseobacterium. The organism contains menaquinone MK-6 as the predominant isoprenoid quinone and 15 : 0 iso (43 %), 17 : 1 isoomega9c (17.5 %) and 17 : 0 iso 3-OH (16.6 %) as the major fatty acids. Phylogenetically, the closest relatives of strain Soil-3-27(T) are Chryseobacterium daecheongense, Chryseobacterium defluvii and Chryseobacterium taichungense with 96.7-97.2 % sequence similarity. DNA-DNA hybridization showed relatedness values of 8.5-24.2 % with these species. The DNA G+C content is 36.8 mol%. Strain Soil-3-27(T) is clearly distinguishable from other Chryseobacterium species and represents a novel species, for which the name Chryseobacterium taiwanense sp. nov. is proposed. The type strain is strain Soil-3-27(T) (=BCRC 17412(T)=IAM 15317(T)=LMG 23355(T)).