State transitions in the cyanobacterium Synechococcus elongatus 7942 involve reversible quenching of the photosystem II core

Cyanobacteria use chlorophyll and phycobiliproteins to harvest light. The resulting excitation energy is delivered to reaction centers (RCs), where photochemistry starts. The relative amounts of excitation energy arriving at the RCs of photosystem I (PSI) and II (PSII) depend on the spectral composition of the light. To balance the excitations in both photosystems, cyanobacteria perform state transitions to equilibrate the excitation energy. They go to state I if PSI is preferentially excited, for example after illumination with blue light (light I), and to state II after illumination with green-orange light (light II) or after dark adaptation. In this study, we performed 77-K time-resolved fluorescence spectroscopy on wild-type Synechococcus elongatus 7942 cells to measure how state transitions affect excitation energy transfer to PSI and PSII in different light conditions and to test the various models that have been proposed in literature. The time-resolved spectra show that the PSII core is quenched in state II and that this is not due to a change in excitation energy transfer from PSII to PSI (spill-over), either direct or indirect via phycobilisomes.     

Development of a biodegradable coating formulation based on the biological characteristics of the Iranian Ultra-filtrated cheese

Type and concentration of edible components, are two main factors which can be affected the chemical, microbial, quality, sensory properties and storage life of coated cheese. In this work, to optimize the concentrations of chitosan and Natamycin for coating Iranian white UF cheese response surface methodology was used. The effects of main edible coating components, chitosan (0.5–2.5%, w/w) and Natamycin (5–20 ppm) on pH, TSS, bacterial total count, yeast and mould population and starter of coated cheese were studied up to 3 weeks after storage at 4?±?2 °C. The obtained results indicated that the second-order polynomial models could be successfully generated with high coefficient of determination (R²?≥?0.9153) using experimental data for all the studied response variables. The optimum concentrations of chitosan and Natamycin were obtained at 1.6% w/w and 18.5 ppm, respectively which the predicted values for pH, TSS, bacterial total count, yeast and mould population and starter were 4.5, 37%, 12 cfu, 14 cfu and 346 cfu, respectively. The verification test was done at obtained optimum concentrations of the main edible components and the statistical analysis indicated insignificant (p?>?0.05) differences between the predicted and experimental values of the response variables.     

Acetyl-<Emphasis Type="SmallCaps">l</Emphasis>-Carnitine Attenuates Arsenic-Induced Oxidative Stress and Hippocampal Mitochondrial Dysfunction

Augmentation of mitochondrial oxidative stress through activating a series of deadly events has implicated as the main culprit of arsenic toxicity and therapeutic approaches based on improving mitochondrial function hold a great promise for attenuating the arsenic-induced toxicity. Acetyl-l-carnitine (ALC) through balancing the coenzyme A (CoA)/acyl-CoA ratio plays an important role in mitochondrial metabolism and thereby can help protect hippocampal neurons from oxidative damage. In the present study, we aimed to explore the effect of arsenic interactions on the mitochondrial function in the hippocampus of rats. Rats were randomly divided into five groups of control (distilled water), sodium arsenite (NaAsO₂, 20 mg/kg), and co-treatment of NaAsO₂ with various doses of ALC in three groups (100, 200, 300 mg/kg) and were treated orally for 21 consecutive days. Our results point out that arsenic exposure caused oxidative stress in rats’ hippocampus, which led to the reactive oxygen species (ROS) generation, mitochondrial swelling, the collapse of the mitochondrial membrane potential, and release of cytochrome c. It also altered Bcl-2/Bax expression ratio and increased caspase-3 and caspase-9 activities. Furthermore, arsenic exposure via activation of NF-κB and microglia increased inflammation. ALC could concentration-dependently counteract the arsenic-induced oxidative stress, modulate the antioxidant defense capacity, and improve mitochondrial functions. In addition, ALC decreased the expression of both death-associated proteins and of inflammatory markers. These findings indicate that ALC improved the arsenic-induced hippocampal mitochondrial dysfunction which underlines the importance of ALC in providing a possible therapeutic strategy for the prevention of arsenic-induced neurodegeneration.     

Association of two groups of phytoplasma with various symptoms in some wooden and herbaceous plants

During 2015–2016, wooden and herbaceous plants growing in parks, boulevards, fields, gardens and forests in Khuzestan province, southwestern Iran, were visually inspected for symptoms resembling phytoplasma. Fifty‐one symptomatic samples from nine different species and one symptomless sample from each plant were collected. Leaf midribs, petioles and the parts of stem cambium were separated and freeze‐dried. Total DNA was extracted using CTAB‐based method and tested for phytoplasma using a nested PCR assay. The expected size amplicons of 16S rDNA were sequenced and compared to those of reference phytoplasmas by BLASTn search and phylogenetic analysis. The consensus 16S rDNA sequence of the detected phytoplasma in narrow cattail related to reference phytoplasma group 16SrVI, “Candidatus Phytoplasma trifolii” while in the other plants were related to reference phytoplasma subgroup 16SrII–D, “Candidatus Phytoplasma aurantifolia.” All isolates showed 98%–99% sequence identity to members of their reference groups. To our knowledge, this is the first report of “Candidatus Phytoplasma aurantifolia”‐related strains infecting the plants of Acacia salicina, Alternanthera ficoidea, Melaleuca citrine, Citrus aurantium throughout the world and Celosia christata in Iran. Furthermore, this study is the first to report the association of a “Candidatus Phytoplasma trifolii”‐related strain with Typha angustifolia worldwide.     

Phylogeography of Walton’s Mudskipper,Periophthalmus waltoni Koumans, 1941 (Perciformes: Gobiidae), from the Persian Gulf and Gulf of Oman

Mudskippers are amphibious air breathing fish with terrestrial adaptations in contrast to entirely aquatic fish. They are adapted to living on mudflats and show morphological, physiological, and behavioural features that could affect their phylogeny and phylogeography. A comparative genetic analysis was carried out on 100 specimens of the mudskipper Periophthalmus waltoni Koumans, 1941 from eight different sites along the coast of the Persian Gulf and Gulf of Oman. Phylogeographic inference based on two mitochondrial markers (Cyt b and D-loop) suggests that P. waltoni populations are divided into two well-divergent clades western and eastern. This is likely related to the geohydrological history of the area during the last Pleistocene glaciations. The regional phylogeographies are apparently also influenced by ecological and geographical barriers such as salinity, water current, and the geographic position of the Strait of Hormuz.     

Eighty Years of <Emphasis Type="Italic">Mycopathologia</Emphasis>: A Retrospective Analysis of Progress Made in Understanding Human and Animal Fungal Pathogens

Mycopathologia was founded in 1938 to ‘diffuse the understanding of fungal diseases in man and animals among mycologists.’ This was an important mission considering that pathogenic fungi for humans and animals represent a tiny minority of the estimated 1.5–5 million fungal inhabitants on Earth. These pathogens have diverged from the usual saprotrophic lifestyles of most fungi to colonize and infect humans and animals. Medical and veterinary mycology is the subdiscipline of microbiology that dwells into the mysteries of parasitic, fungal lifestyles. Among the oldest continuing scientific publications on the subject, Mycopathologia had its share of ‘classic papers’ since the first issue was published in 1938. An analysis of the eight decades of notable contributions reveals many facets of host–pathogen interactions among 183 volumes comprising about 6885 articles. We have analyzed the impact and relevance of this body of work using a combination of citation tools (Google Scholar and Scopus) since no single citation metric gives an inclusive perspective. Among the highly cited Mycopathologia publications, those on experimental mycology accounted for the major part of the articles (36%), followed by diagnostic mycology (16%), ecology and epidemiology (15%), clinical mycology (14%), taxonomy and classification (10%), and veterinary mycology (9%). The first classic publication, collecting nearly 200 citations, appeared in 1957, while two articles published in 2010 received nearly 150 citations each, which is notable for a journal covering a highly specialized field of study. An empirical analysis of the publication trends suggests continuing interests in novel diagnostics, fungal pathogenesis, review of clinical diseases especially with relevance to the laboratory scientists, taxonomy and classification of fungal pathogens, fungal infections and carriage in pets and wildlife, and changing ecology and epidemiology of fungal diseases around the globe. We anticipate that emerging and re-emerging fungal pathogens will continue to cause significant health burden in the coming decades. It remains vital that scientists and physicians continue to collaborate by learning each other’s language for the study of fungal diseases, and Mycopathologia will strive to be their partner in this increasingly important endeavor to its 100th anniversary in 2038 and beyond.     

Investigate of AQP gene expression in the liver of mice after ischemia–reperfusion

Ischemia–reperfusion (IR) injury usually occurs during liver transplantation. Aquaporins (AQPs) are transmembrane channels that facilitate water permeability through cell membranes and are essential for the regulation of water homeostasis. Changes in the AQPs expression have been correlated with several inflammatory diseases. Less is known about AQPs expression in hepatic ischemia reperfusion injury. To clarify the roles of AQPs in IR injury, in this current study we examined the gene expression patterns of AQP1, 8 and 9 in the liver after IR injury. Male balb/c mice were exposed to partial (70%) hepatic ischemia for 65 min and then randomized into five groups of reperfusion [0 h (A), 8 h (B), 1 day (C), 3 days (D), and 7 days (E)]. A surgical group was also selected as the sham group. Serum and liver tissue samples were collected for evaluation of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and liver histopathology. Real time PCR was performed to evaluate the AQPs expression. I/R injury resulted in a significant increase in ALT and AST (p?<?0.05) compared to sham mice in each group. The gene expression of AQPs was significantly increased in the IR group compared with the sham group (p?<?0.05). AQP8 and AQP1 after 8 h (group B) showed the highest gene expression in comparison with other groups, but the highest level of AQP9 gene expression was observed after 1 day (group C). Pathologic changes in the liver after reperfusion were confirmed the IR. In the IR group cytoplasmic vacuolization, inflammatory cell infiltration and focal necrosis were detected. In conclusion, our findings indicated that the damage caused by ischemia–reperfusion in the liver can change the expression of AQP genes, which can interfere with hepatocellular homeostasis and their function. Upregulation of AQP1, 8 and 9 could contribute to the development of hepatocellular swelling after hepatic IR injury.     

Comparative nutritional and mycochemical contents,biological activities and LC/MS screening of tuber from new recipe cultivation technique with wild type tuber of tiger’s milk mushroom of species <Emphasis Type="Italic">Lignosus rhinocerus</Emphasis>

Tiger’s milk mushroom is known for its valuable medicinal properties, especially the tuber part. However, wild tuber is very hard to obtain as it grows underground. This study first aimed to cultivate tiger’s milk mushroom tuber through a cultivation technique, and second to compare nutritional and mycochemical contents, antioxidant and cytotoxic activities and compound screening of the cultivated tuber with the wild tuber. Results showed an increase in carbohydrate content by 45.81% and protein content by 123.68% in the cultivated tuber while fat content reduced by 13.04%. Cultivated tuber also showed an increase of up to 64.21% for total flavonoid-like compounds and 62.51% of total β-d-glucan compared to the wild tuber. The antioxidant activity of cultivated tuber and wild tuber was 760 and 840 µg mL^?1, respectively. The cytotoxic activity of boiled water extract of cultivated tuber against a human lung cancer cell line (A549) was 65.50?±?2.12 µg mL^?1 and against a human breast cancer cell line (MCF7) was 19.35?±?0.11 µg mL^?1. β-d-glucan extract from the purification of boiled water extract of cultivated tuber showed cytotoxic activity at 57.78?±?2.29 µg mL^?1 against A549 and 33.50?±?1.41 µg mL^?1 against MCF7. However, the β-glucan extract from wild tuber did not show a cytotoxic effect against either the A549 or MCF7 cell lines. Also, neither of the extracts from cultivated tuber and wild tuber showed an effect against a normal cell line (MRC5). Compound profiling through by liquid chromatography mass spectrometry (LC/MS) showed the appearance of new compounds in the cultivated tuber. In conclusion, our cultivated tuber of tiger’s milk mushroom using a new recipe cultivation technique showed improved nutrient and bioactive compound contents, and antioxidant and cytotoxic activities compared to the wild tuber. Further investigations are required to obtain a better quality of cultivated tuber.     

Production of nanocalcite crystal by a urease producing halophilic strain of <Emphasis Type="Italic">Staphylococcus saprophyticus</Emphasis> and analysis of its properties by XRD and SEM

Cementation of salt-containing soils can be achieved by salt-tolerant or halophilic calcite precipitation bacteria. Therefore, the isolation of calcite-producing bacteria in the presence of salt is the first step in the microbial cementation of saline soils. Urease producing bacteria can cause calcite nano-crystals to precipitate by producing urease in the presence of urea and calcium. The purpose of this study was to isolate urease producing halophilic bacteria in order to make calcite precipitate in saline soil. The calcite and the properties of the strains were further analyzed by X-ray diffraction (XRD) and scanning electron microscope equipped with an energy dispersive X-ray detector. In this study, a total of 110 halophilic strains were isolated, from which 58 isolates proved to have the ability of urease production. Four strains were identified to produce nano-calcite using urease activity in the precipitation medium. The XRD studies showed that the size of these particles was in the range of 40–60 nm. Strain H3 revealed that calcite is mostly produced in the precipitation medium containing 5% salt in comparison with other strains. This strain also produced calcite precipitates in the precipitation medium containing 15% salt. Phylogenetic analysis indicated that these isolates are about 99–100% similar to Staphylococcus saprophyticus.