Acquisition of de novo spacer sequences confers CRISPR-Cas with a memory to defend against invading genetic elements. However, the mechanism of regulation of CRISPR spacer acquisition remains unknown. Here we examine the transcriptional regulation of the conserved spacer acquisition genes in Type I-A of Sulfolobus islandicus REY15A. Csa3a, a MarR-like transcription factor encoded by the gene lo...

The 16S-23S rRNA intergenic spacer regions of 14 strains representing the 14 serovars of Ureaplasma urealyticum were amplified by PCR and sequenced for genetic differentiation between the two biovars Parvo and T960. Although the spacer region of the Parvo and T960 biovars comprised 302 nucleotides and lacked spacer tRNA genes, 15 nucleotides were different between the two biovars. The four nucl...

This paper describes a simple and reliable method of improving the surface insulation strength of a spacer used in vacuum. The method is to roughen the spacer surface to an average roughness R higher than 1 or 2 m. The material of the spacer a examined is SiO , PMMA, PTFE or Al O and their shape is a right cylinder with 2 2 3 10 mm in height and 54 mm in diameter. The spacer is subjected to a r...

BACKGROUND The aim of this study was to extend previous in vitro observations regarding the effects of multiple actuations of aerosols into spacer devices, delayed inhalation, and antistatic treatment of spacer devices on the amount of drug delivered for inhalation. An in vivo study of lung bioavailability of salbutamol from a large volume (Volumatic) spacer was conducted. METHODS Ten healthy...

dunaliella is a green halotolerant microalga, which has several industrial applications e.g. β-carotene production. identification of different dunaliella species has been carried out by morpho-physiological and recently molecular studies. to achieve an improved understanding of taxonomy, these studies are required to be in linkage. the present study describes molecular and specific morpho-phys...

theplant pathogenic phytophthora drechsleri is morphologically similar to some other non-papillate phytophthora spp., especially p. melonis, and it is difficult to discriminate these convergent taxa. it seems that the iranian putative p. drechsleri isolates from different cucurbit species have been generally misidentified and their characteristics do not match with p. drechsleri. in order to co...