Natural transformation in Gram-negative bacteria thriving in extreme environments: from genes and genomes to proteins,structures and regulation

Extremophiles - Extremophilic prokaryotes live under harsh environmental conditions which require far-reaching cellular adaptations. The acquisition of novel genetic information via natural...     

Is carbonic anhydrase inhibition useful as a complementary therapy of Covid-19 infection?

The ongoing Covid-19 is a contagious disease, and it is characterised by different symptoms such as fever, cough, and shortness of breath. Rising concerns about Covid-19 have severely affected the healthcare system in all countries as the Covid-19 outbreak has developed at a rapid rate all around the globe. Intriguing, a clinically used drug, acetazolamide (a specific inhibitor of carbonic anhydrase, CA, EC 4.2.1.1), is used to treat high-altitude pulmonary oedema (HAPE), showing a high degree of clinical similarities with the pulmonary disease caused by Covid-19. In this context, this preliminary study aims to provide insights into some factors affecting the Covid-19 patients, such as hypoxaemia, hypoxia as well as the blood CA activity. We hypothesise that patients with Covid-19 problems could show a dysregulated acid–base status influenced by CA activity. These preliminary results suggest that the use of CA inhibitors as a pharmacological treatment for Covid-19 may be beneficial.     

Evaluation of the androgenic competence of 66 wild Turkish Vaccaria hispanica (Mill.) Rauschert genotypes through microspore culture

One of the most remarkable natural plants is Vaccaria hispanica (Mill.) Rauschert, which has a high economic, medicinal and industrial potential due to its valuable compounds. However, it is mostly an underused plant worldwide. To implement doubled haploid technology in plant breeding programs and exploit its potential, first knowing the particulars of the species is necessary. This study was aimed to explore the androgenic potential of different wild Turkish V. hispanica genotypes collected from different Turkish regions, as a starting point to identify bottlenecks to solve in future studies. As to induction of microspore embryogenesis, nearly all of them responded, with efficiencies reaching 300 embryos/100 buds in some cases. However, we also found three main bottlenecks. First, the presence of foam-producing saponins in flowers prevented an efficient isolation of microspores. Second, embryos showed a reduced ability to germinate. Third, a dense network of hairy roots prevented the formation of a true, fully functional root system. Together, these drawbacks led to the production of very few DH plants. The presence of rhizogenic endophytes may be the cause of most of these problems, which opens the door for possible solutions.

     

Locally Epistatic Genomic Relationship Matrices for Genomic Association and Prediction

In plant and animal breeding studies a distinction is made between the genetic value (additive plus epistatic genetic effects) and the breeding value (additive genetic effects) of an individual since it is expected that some of the epistatic genetic effects will be lost due to recombination. In this article, we argue that the breeder can take advantage of the epistatic marker effects in regions of low recombination. The models introduced here aim to estimate local epistatic line heritability by using genetic map information and combining local additive and epistatic effects. To this end, we have used semiparametric mixed models with multiple local genomic relationship matrices with hierarchical designs. Elastic-net postprocessing was used to introduce sparsity. Our models produce good predictive performance along with useful explanatory information.     

Association between serum irisin concentration and ischemic stroke: From etiology to clinic

BackgroundTo investigate the relationship between irisin levels in serum and classification of subtype of acute ischemic stroke, National Institutes of Health Stroke Scale (NIHSS) and Modified Rankin Score (mRS) at the time of discharge from the hospital in Turkish patients who had their first acute ischemic stroke (AIS).MethodsSerum irisin levels were measured using enzyme linked immunosorbent assay (ELISA) 180 patients who applied to emergency department with the diagnosis of AIS from May 2021 to November 2021.ResultsA significant relationship was found between serum irisin levels and ischemic stroke aetiological factors (TAOST) (p=0.017). Increased serum irisin levels were detected in patients without neurological deficits with localization value than those with it (p<0.01). Serum irisin levels also have a negative correlation with high-density lipoprotein (HDL) value in ischemic stroke (r: -0.272, p<0.01).ConclusionsHigh serum irisin levels found in patients with stroke attributed to small vessel disease and in patients with ischemic stroke in whom we did not find any neurological deficits with a localization value. The results of the study show that serum irisin levels have an important role in the etiology of ischemic stroke. Although the question how the irisin is involved in the course of ischemic stroke and what the clinical reflection has not been answered, these findings are a pioneering study on this subject.     

Suppression of generalized seizures activity by intrathalamic 2-chloroadenosine application

In the present study, we investigated the effects of micro-injecting 2-chloroadenosine (2-CADO; an adenosine receptor agonist) into the thalamus alone and with theophylline (a nonspecific adenosine receptor antagonist) pretreatment on pentylenetetrazol (PTZ)-induced tonic-clonic seizures in male Wistar albino rats. Following intrathalamic 2-CADO injection alone or theophylline pretreatment, 50 mg kg(-1) PTZ was given ip after 1 and 24 hrs. The duration of epileptic seizure activity was recorded by cortical electroencephalogram (EEG), and seizure severity was behaviorally scored. Intrathalamic 2-CADO administration induced significant decreases in both seizure duration and seizure severity scores at 1 and 24 hrs, but the effects were more abundant on the seizures induced after 24 hrs. On the other hand, pretreatment with theophylline prevented the inhibitor effect of 2-CADO on seizure activity and increased both seizure duration and seizure scores. Present results suggest that the activation of adenosine receptors in the thalamus may represent another anticonvulsant/modulatory site of adenosine action during the course of the PTZ-induced generalized tonic-clonic seizures and provide additional data for the involvement of the adenosinergic system in the generalized seizures model.     

Type II Fatty Acid Biosynthesis, a New Approach in Antimalarial Natural Product Discovery

Malaria, one of the most problematic infectious diseases worldwide, is on the rise. The absence of an effective vaccine and the spread of drug-resistant strains of Plasmodium clearly indicate the necessity for the development of new chemotherapeutic agents and the identification of novel targets. The recent discovery of a relict, non-photosynthetic plastid-like organelle, the so-called apicoplast, in Plasmodium has opened up new avenues in malaria research. It also initiated the Plasmodium falciparum genome sequencing project, which revealed a number of biochemical pathways previously unknown to Plasmodium, i.e. cytosolic shikimate pathway, apicoplastic type II fatty acid, non-mevalonate isoprene and haem biosyntheses. Since these vital biosynthetic processes are absent in humans or fundamentally different from those found in humans, they represent excellent targets for pharmaceutical interventions. We are interested in the type II fatty acid synthase (FAS II) system of malaria parasite and focus on the FabI enzyme, the only known enoyl-ACP reductase in Plasmodium involved in the final reduction step of the fatty acid chain elongation cycle. Here we describe the general aspects of fatty acid biosynthesis, its essentiality to the malaria parasite and our continuing efforts to discover in Turkish medicinal plants natural antimalarial agents, which specifically target the plasmodial FabI enzyme.Phytochemical Society of Europe (PSE)-Pierre Fabre Prize 2004 Lecture