The genetic basis of sexual isolation that contributes to speciation is one of the unsolved questions in evolutionary biology. Drosophila ananassae and Drosophila pallidosa are closely related, and postmating isolation has not developed between them. However, females of both species discriminate their mating partners, and this discrimination contributes to strong sexual isolation between them. ...

Objective(s) Staphylococcus aureus is a common cause of human infection, and emergence of vancomycin-resistance S. aureus  is a great concern for treatment of methicillin-resistant S. aureus,(MRSA) in recent years (MRSA). Here, we report the isolation of high-level VRSA. Materials and Methods S. aureus was isolated from foot ulcer of a diabetic woman in Tehran, Iran. Antibiotic susceptibilit...

The claR of Streptomyces clavuligerus in the clavulanic acid gene cluster encodes a transcriptional regulator that controls clavulanic acid biosynthesis. The main goal of this study was isolation and molecular detection of the claR gene and its cloning in the Streptomyces specific vector (pMA:: hyg). By cinsideration of the claR gene’s start codon, the specific primers were designed. After geno...

The transformation-associated recombination (TAR) cloning technique allows selective and accurate isolation of chromosomal regions and genes from complex genomes. The technique is based on in vivo recombination between genomic DNA and a linearized vector containing homologous sequences, or hooks, to the gene of interest. The recombination occurs during transformation of yeast spheroplasts that ...

introduction and aims: helicobacter pylori commonly is associated with gastritis: but only sometimes it causes clinically significant diseases such as gastric and duodenal ulcer. the development of disease depends on the virulence of the infecting h. pylori strain, the susceptibility of the host, and environment co-factors. the cytotoxin associated protein encoded by caga gene is an important v...

Background: Campylobacter jejuni and Campylobacter coli are zoonotic bacteria which are frequently associated with human diarrhea. Sharing of the cytolethal distending toxin (cdt) genes in Campylobacter is common and is considered species specific. OBJECTIVES: In this study we focused on detecting the presence of cdt gene in C. jejuni and C. coli isolated from broilers, turkeys and quails of Ir...

Reproductive isolation is a key feature that forms barriers to gene flow between distinct plants. In orchids, prezygotic reproductive isolation has been considered to be strong, because their associations with highly specific pollinators. In this study, the reproductive ecology and reproductive isolation of two sympatric Habenaria species, H. davidii and H. fordii, was investigated by floral ph...

background and objectives: annexin is the common name for genes and proteins that were identified as calcium-dependent phospholipid-binding proteins. recently a more complex set of functions has been recognized for this superfamily of proteins including in vesicle trafficking, cell division, apoptosis, calcium signalling, mineralization, crystal nucleation inside the extracellular organelles-ma...

Environmental differences can cause reproductive isolation to evolve. Distinct habitats can be particularly important for the evolution of genetically based sexual isolation, which occurs when divergent preferences and mating traits reduce mating between species. Yet, we know little about environmental effects on the potentially plastic expression, and thus the current maintenance, of sexual is...