The surface layer of the oceans and other aquatic environments contains many bacteria that range in activity, from dormant cells to those with high rates of metabolism. However, little experimental evidence exists about the activity of specific bacterial taxa, especially rare ones. Here we explore the relationship between abundance and activity by documenting changes in abundance over time and ...

For the analysis of microbial community structure based on 16S rDNA sequence diversity, sensitive and robust PCR amplification of 16S rDNA is a critical step. To obtain accurate microbial composition data, PCR amplification must be free of bias; however, amplifying all 16S rDNA species with equal efficiency from a sample containing a large variety of microorganisms remains challenging. Here, we...

Nodule isolates from 11 species of wild legumes in north-western China were characterized by numerical taxonomy, PCR-based 16S rRNA gene RFLP and sequence analyses, DNA-DNA hybridization, restriction patterns of nodDAB and nifH genes, and symbiotic properties. Based on the results of numerical taxonomy, most of the 35 new isolates were grouped into five clusters (clusters 7, 9, 12, 14 and 15). ...

In a recent case of scrub typhus in Australia, Orientia tsutsugamushi isolated from the patient's blood was tested by sequence analysis of the 16S rDNA gene. The sequence showed a strain of O. tsutsugamushi that was quite different from the classic Karp, Kato, and Gilliam strains. The new strain has been designated Litchfield.

Canine anaplasmosis is regarded as an infection by Anaplasma platys rather than zoonotic Anaplasma phagocytophilum in subtropical areas based on the assumption that the common dog tick species is Rhipicephalus sanguineus, which transmits E. canis and presumably A. platys. We investigated asymptomatic dogs and dog ticks from 16 communities in Nantou County, Taiwan to identify common dog tick spe...

Two Paenibacillus macerans strains, JCM 2500T and MCRI 12, exhibited two types of 16S rDNA copies in their genomes, accompanied by a length difference of 12 bp at positions 203 to 214 (Escherichia coli numbering). The long-type sequences were newly identified for P. macerans 16S rDNA, and the copy numbers were different between the two strains. Both types of 16S rRNA were expressed in each stra...

Autotrophic ammonia oxidizer (AAO) populations in soils from native, tilled, and successional treatments at the Kellogg Biological Station Long-Term Ecological Research site in southwestern Michigan were compared to assess effects of disturbance on these bacteria. N fertilization effects on AAO populations were also evaluated with soils from fertilized microplots within the successional treatme...

The diversity associated with a microbial mat sample collected from a deep-sea hydrothermal vent on the Southern East Pacific Rise was determined using a molecular phylogenetic approach based on the comparison of sequences from the small subunit ribosomal RNA gene (16S rDNA). The DNA was extracted from the sample and the 16S rDNA was amplified by PCR. Sixteen different phylotypes were identifie...

Nghiên cứu được thực hiện với mục đích phân lập và tuyển chọn dòng vi khuẩn có khả năng giải protein ức chế Vibrio spp. Khả bằng phương pháp nhỏ giọt khuếch tán qua giếng. đã 10 từ nước mắm truyền thống, trong đó 7 4 Dòng là NM2.1 đường kính vòng lớn mạnh nhất những nghiên cứu. Qua quan sát hình thái lạc, tế bào trình tự đoạn gene 16S rDNA xác định Bacillus sp. độ tương đồng 99,71% chịu mặn đến...