Until the 1980s the diagnosis of specific etiologic agents of infectious diseases rested with their isolation in vitro and identification by analysis of their phenotypic characteristics. In the 1970s the concept of a microbial species evolved from phenotypic analysis to nucleic acid homology. Currently, nucleic acid sequences specific for a given species are being isolated and amplified and uti...

bstract—Most gap junctions between neurons in mammaian retina contain abundant connexin36, often in association ith the scaffolding protein zonula occludens-1. We now nvestigate co-association of connexin36, zonula occludens-1, onula occludens-2 and Y-box transcription factor 3 (zonula ccludens-1-associated nucleic acid-binding protein) in ouse and rat retina. By immunoblotting, zonula occluden...

chlamydia trachomatis is the most prevalent sexually transmitted bacterial infection, with an estimated annual worldwide incidence of 50 million cases. a large proportion of those infected, particularly women, are asymptomatic, and these individuals serve as a major reservoir of infection. women are also at risk for serious reproductive tract complications with significant morbidity. in an effo...

there are significant challenges associated with qualitative and quantitative nucleic acid tests performed in diagnostic laboratories. the development of internationally available certified reference materials which can be traced to reference measurements will contribute to a better understanding of the performance characteristics of nucleic acid tests and enhance reliability and comparability ...

in this study at first , an azo dye, 2,7- naphthalenediol, 2-[(4-bromophenyl)azo (bpand) as a ligand has been synthesized by addition of p-bromoaniline to the modified montomorillonite k10 clay. this ligand was characterized using 1h-nmr, uv-vis and ir spectroscopies. subsequently, its interaction with calf thymus deoxyribonucleicacid ,ct-dna was investigated in 5 mm phosphate buffer solution, ...

We show that nucleic acid structures may be conveniently and inexpensively characterized by their UV thermal difference spectra. A thermal difference spectrum (TDS) is obtained for a nucleic acid by simply recording the ultraviolet absorbance spectra of the unfolded and folded states at temperatures above and below its melting temperature (T(m)). The difference between these two spectra is the ...

Ions surround nucleic acids in what is referred to as an ion atmosphere. As a result, the folding and dynamics of RNA and DNA and their complexes with proteins and with each other cannot be understood without a reasonably sophisticated appreciation of these ions' electrostatic interactions. However, the underlying behavior of the ion atmosphere follows physical rules that are distinct from the ...

Amino acid sequences homologous to 259KLVGKL (X)16KLLR284 of human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) are conserved in several nucleotide polymerizing enzymes. This amino acid motif has been identified in the crystal structure model as an element of the enzyme's nucleic acid binding apparatus. It is part of the helix-turn-helix structure, alpha H-turn-alpha I, within...