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Ghahremaninejad F.,Kharazmi University | Khalili Z.,Kharazmi University | Maassoumi A.A.,Iranian Research Institute of Forests and Rangelands | Mirzaie-Nodoushan H.,Iranian Research Institute of Forests and Rangelands | Riahi M.,Iranian Biological Resource center
American Journal of Botany | Year: 2012

Premise of the study: The classification of the genus Salix has historically been intrinsically difficult due to its propensity toward plasticity and high variation in diagnostic morphological characters. We investigated leaf epidermal characteristics, focusing on the stomatal apparatus because it may provide critical insights into the evolution and taxonomy of Salix and its closely related genera. • Methods: Light microscopy was used to examine the leaf epidermal features in 32 taxa of Salix. • Key results: Characters such as shape, size, and density of stomatal complexes were very useful in differentiating Salix species. Variation in features of stomatal apparatus in Salix is wider than previously known. Moreover, the type of stomatal complex proved to be very helpful in discriminating Chosenia as members of the genus Salix. • Conclusions: The results of the present study support the placement of Chosenia within Salix and the combining of subgenera Chamaetia and Vetrix because of similarities in their unique stomatal apparatus. © 2012 Botanical Society of America. Source

Dolatyari A.,Iranian Biological Resource center | Valles J.,University of Barcelona | Naghavi M.R.,University of Tehran | Shahzadeh Fazeli S.A.,Iranian Biological Resource center | Shahzadeh Fazeli S.A.,Royan Institute for Reproductive Biomedicine
Plant Systematics and Evolution | Year: 2013

Somatic chromosome numbers of 47 accessions representing 28 Artemisia species are provided from Iran. Two basic chromosome numbers, x = 8, 9, each with diploid, tetraploid and hexaploid levels, were found. Different chromosome numbers, 2n = 16, 16 + 1B, 16 + 5B, 32, 48, and 2n = 18, 18 + 1B, 19, 36, 36 + 1B, 36 + 2B, 37, 49 + 2B, 49 + 3B, 51 + 6B, 54, 54 + 1B, 54 + 3B, 54 + 5B, in studied accessions were identified. Chromosome numbers are reported for the first time in three species, counts in four species are new for Iran, and other counts have been thoroughly compared to previous data. Forty percent of the studied accessions are polyploid and B-chromosome(s) are reported in 17 % of accessions. Aneuploidy and aneusomy are other relevant cytological phenomena. Some karyological parameters, total karyotype length, karyotype formula, mean value of centromeric indices, mean arm ratio, A 1 and A 2 indices, were estimated to characterize the karyotypes numerically. A 1 and A 2 indices showed that karyotypes tend to be asymmetric in polyploid and dysploid taxa. PCA analysis of all karyological parameters has shown some systematic and evolutionary implications. The consideration of all these chromosome numbers and cytogenetic mechanisms has led us to infer the different patterns of chromosomal evolution in the genus. © 2013 Springer-Verlag Wien. Source

Nikfarjam L.,Iranian Biological Resource center | Farzaneh P.,Iranian Biological Resource center
Cell Journal | Year: 2012

One of the main problems in cell culture is mycoplasma infection. It can extensively affect cell physiology and metabolism. As the applications of cell culture increase in research, industrial production and cell therapy, more concerns about mycoplasma contamination and detection will arise. This review will provide valuable information about: 1. the ways in which cells are contaminated and the frequency and source of mycoplasma species in cell culture; 2. the ways to prevent mycoplasma contamination in cell culture; 3. the importance of mycoplasma tests in cell culture; 4. different methods to identify mycoplasma contamination; 5. the consequences of mycoplasma contamination in cell culture and 6. available methods to eliminate mycoplasma contamination. Awareness about the sources of mycoplasma and pursuing aseptic techniques in cell culture along with reliable detection methods of mycoplasma contamination can provide an appropriate situation to prevent mycoplasma contamination in cell culture. Source

Ghafoori H.,Guilan University | Askari M.,Guilan University | Sarikhan S.,Iranian Biological Resource center
Extremophiles | Year: 2016

This study reports the purification and characterization of an extracellular haloalkaline serine protease from the moderately halophilic bacterium, Bacillus iranensis, strain X5B. The enzyme was purified to homogeneity by acetone precipitation, ultrafiltration and carboxymethyl (CM) cation exchange chromatography, respectively. The purified protease was a monomeric enzyme with a relative molecular mass of 48–50 kDa and it was inhibited by PMSF indicating that it is a serine-protease. The optimum pH, temperature and NaCl concentration were 9.5, 35 °C and 0.98 M, respectively. The enzyme showed a significant tolerance to salt and alkaline pH. It retained approximately 50 % of activity at 2.5 M NaCl and about 70 % of activity at highly alkaline pH of 11.0; therefore, it was a moderately halophilic and also can be activated by metals, especially by Ca2+. The specific activity of the purified protease was measured to be 425.23 μmol of tyrosine/min per mg of protein using casein as a substrate. The apparent Km and Vmax values were 0.126 mM and 0.523 mM/min, respectively and the accurate value of kcat was obtained as 3.284 × 10−2 s−1. These special and important characteristics make this serine protease as valuable tool for industrial applications. © 2015, Springer Japan. Source

Amoozegar M.A.,University of Tehran | Shahinpei A.,Iranian Biological Resource center | Sepahy A.A.,Islamic Azad University at North Tehran | Makhdoumi-Kakhki A.,Ferdowsi University of Mashhad | And 3 more authors.
International journal of systematic and evolutionary microbiology | Year: 2014

A novel Gram-stain-negative, aerobic, non-endospore-forming, non-pigmented, rod-shaped, slightly halophilic bacterium, designated GBPy5(T), was isolated from aquatic plants of the Gomishan wetland, Iran. Cells of strain GBPy5(T) were motile. Growth occurred with between 1 and 10% (w/v) NaCl and the isolate grew optimally with 3% (w/v) NaCl. The optimum pH and temperature for growth of the strain were pH 8.0 and 30 °C, respectively, while it was able to grow over a pH range of 6.5-9.0 and a temperature range of 4-35 °C. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain GBPy5(T) is a member of the genus Pseudomonas forming a monophyletic branch. The novel strain exhibited 16S rRNA gene sequence similarity of 95.4% with type strains of Pseudomonas guariconensis PCAVU11(T) and Pseudomonas sabulinigri J64(T), respectively. The major cellular fatty acids of the isolate were C18:1ω7c (37.8%), C16:0 (14.9%), C16:1ω7c (12.9%), C12:0 3-OH (7.1%) and C12:0 (7.0%). The polar lipid pattern of strain GBPy5(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and one phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The G+C content of the genomic DNA of strain GBPy5(T) was 59.2 mol%. On the basis of the phenotypic and phylogenetic data, strain GBPY5(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salegens sp. nov. is proposed. The type strain is GBPy5(T) ( = IBRC-M 10762(T) = CECT 8338(T)). IUMS. Source

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