Class I DISARM provides anti-phage and anti-conjugation activity by unmethylated DNA recognition

Bacteriophages impose a strong evolutionary pressure on microbes for the development of mechanisms of survival. Multiple new mechanisms of innate defense have been described recently, with the molecular mechanism of most of them remaining uncharacterized. Here, we show that a Class 1 DISARM (defense island system associated with restriction-modification) system from Serratia sp. provides broad protection from double-stranded DNA phages, and drives a population of single-stranded phages to extinction. We identify that protection is not abolished by deletion of individual DISARM genes and that the absence of methylase genes drmMI and drmMII does not result in autoimmunity. In addition to antiphage activity we also observe that DISARM limits conjugation, and this activity is linked to the number of methylase cognate sites in the plasmid. Overall, we show that Class 1 DISARM provides robust anti-phage and anti-plasmid protection mediated primarily by drmA and drmB, which provide resistance to invading nucleic acids using a mechanism enhanced by the recognition of unmethylated cognate sites of the two methylases drmMI and drmMII.

Inactivation of mrpigH Gene in Monascus ruber M7 Results in Increased Monascus Pigments and Decreased Citrinin with mrpyrG Selection Marker

Monascus pigments (MPs) have been used as food colorants for several centuries in Asian countries and are currently used around the world via Asian catering. The MPs biosynthetic pathway has been well-illustrated; however, the functions of a few genes including mrpigH in the MPs gene cluster of M. ruber M7 are still unclear. In the current study, mrpigH was disrupted in Δmrlig4ΔmrpyrG, a highly efficient gene modification system, using mrpyrG as a selection marker, and ΔmrpigHΔmrlig4ΔmrpyrG::mrpyrG and ΔmrpigHΔmrlig4ΔmrpyrG have been obtained. Subsequently, their morphologies, biomasses, MPs and citrinin (CIT) production were analyzed, respectively. These results have revealed that the deletion of mrpigH has significant effects on the morphology and growth of M. ruber M7. Moreover, compared with M. ruber M7, the yields of MPs and CIT were drastically increased and decreased in mrpigH mutants, respectively.

Inactivation of MrPigH in Monascus ruber M7 Results in its Monascus Pigments Increase and Citrinin Decrease with mrpyrG Selection Marker

Monascus pigments (MPs) have been used as food colorants for several centuries in Asian countries and nowadays in the whole world via Asian catering. The MPs biosynthetic pathway has been well-illustrated, however, the functions of a few genes including mrpigH in the MPs gene cluster of M. ruber M7 are still unclear. In current study, mrpigH was disrupted in Δmrlig4ΔmrpyrG, a highly efficient gene modification system, using mrpyrG as a selection marker, and ΔmrpigHΔmrlig4ΔmrpyrG::mrpyrG and ΔmrpigHΔmrlig4ΔmrpyrG have been obtained. Subsequently, their morphologies, biomasses, MPs and citrinin (CIT) production were analyzed, respectively. These results have revealed that the deletion of mrpigH has significant effects on the morphology and growth of M. ruber M7. Moreover, compared with M. ruber M7, the yields of MPs and CIT were drastically increased and decreased in mrpigH mutants, respectively.

Characterization of the Type I Restriction Modification System Broadly Conserved among Group A Streptococci

The advent of whole-genome approaches capable of detecting DNA methylation has markedly expanded appreciation of the diverse roles of epigenetic modification in prokaryotic physiology. For example, recent studies have suggested that DNA methylation impacts gene expression in some streptococci.

Restriction-modification systems and DNA methylation profile of Pectobacterium carotovorum 2A

The methylation profile of Pectobacterium carotovorum 2A genome was studied using the Oxford Nanopore sequencing technology. The specificity of the methylase subunits of the three restriction-modification systems of this strain was determined. Analysis of homologous systems showed the uniqueness of the type I restriction-modification system and the type IV restriction system specific to methylated DNA of this strain. The work confirms the applicability of Oxford Nanopore technology to the analysis of bacterial DNA modifications and is also the first example of such an analysis for Pectobacterium spp.

Knockdown of ubiquitin-like modifier-activating enzyme 2 promotes apoptosis of clear cell renal cell carcinoma cells

Small ubiquitin-related modifier (SUMO) proteins are involved in the development of tumors. Ubiquitin-like modifier-activating enzyme 2 (UBA2) is an important member of the SUMO modification system; however, its role in clear cell renal cell carcinoma (ccRCC) is unclear. Therefore, we investigated the expression and function of UBA2 in ccRCC. Both mRNA and protein expression levels of UBA2 were found to be higher in ccRCC than in normal renal tissues and significantly related to the tumor size, Fuhrman grade, and tumor stage. UBA2 knockdown inhibited ccRCC cell growth, promoted apoptosis in vitro and in vivo, and decreased the abundance of a p53 mutant, c-Myc, and key enzymes of the SUMO modification system. Meanwhile, overexpression of UBA2 had the opposite effects. Overexpression of the p53 mutant or c-Myc alleviated the effects of UBA2 knockdown on ccRCC cell proliferation and apoptosis. In conclusion, targeting UBA2 may have a therapeutic potential against ccRCC.

Conjugation-based genome engineering in Deinococcus radiodurans

D. radiodurans has become an attractive microbial platform for the study of extremophile biology and industrial bioproduction. To improve the genomic manipulation and tractability of this species, the development of tools for whole genome engineering and design is necessary. Here, we report the development of a simple and robust conjugation-based transformation system from E. coli to D. radiodurans allowing for the introduction of stable, replicating plasmids expressing antibiotic resistance markers. Using this method with nonreplicating plasmids, we developed a protocol for creating sequential gene deletions in D. radiodurans by target-ing restriction-modification system genes. Importantly, we demonstrated a conjugation-based method for cloning the large (178 kb), high G+C content MP1 megaplasmid from D. radiodurans in E. coli. The conjugation-based tools described here will facili-tate the development of D. radiodurans strains with synthetic genomes for biological studies and industrial applications.

Epigenetic Regulation of Nostoc punctiforme ATCC 29133 in Response to Nitrogen Availability

Here, we report the restriction modification system of Nostoc punctiforme ATCC 29133, along with its methylated genome sequence, under contrasting nitrate availability. Generated methylation profiles revealed increased methylation for key enzymes of assimilatory nitrate reduction, suggesting that Nostoc punctiforme employs DNA methylation to regulate its nitrogen metabolism.

Zsigeri fájdalom, nocebo-hatások, placebo-analgézia

Összefoglaló. A belső szervek működési zavarai gyakran származnak viselkedési, lelki vagy pszichoszociális okokból, amelyeknek nem mindig vagyunk tudatában. Minthogy ebben a folyamatban egy bonyolult neuronális hálózat játssza a fő szerepet, ezeknek a zavaroknak a diagnózisa és terápiája számos tényező manipulálását igényli. A funkcionális gyomor-bélhuzam rendellenességek (FGID), például az irritábilisbél-szindróma (IBS), jellemző példái ennek: olyan működési zavarokról van szó, amelyek mögött jól detektálható szervi vagy biokémiai elváltozásokat nem találnak. Ilyenkor szükségesnek tűnik a komplex megközelítés, amely többféle szakember együttműködését kívánja meg. Szerepe lehet a pszichés vagy életmód terápiának, a gyógyszeres és fizikai kezelésnek is, és – ahogy ebben a cikkben megmutatjuk – a placebo-terápiának is. Summary. Functional disorders of the internal organs frequently are results of behavioral, mental or psycho-social dysfunctions, although we are usually not conscious about it. A typical example isirritable bowel syndrome (IBS), a characteristic functional gastro-intestinal disorder (FGID), which is regularly accompanied by abdominal pain and irregular intestinal motility and defecation. It has been shown that this disorder cannot be due to a single factor, nor is it a result of a local cause. Recently researchers have proven that malfunction of a complicated neuronal network, including several brain sites, may be responsible for IBS. It is believed now that IBS is the consequence of several nocebo-effects. IBS is a typical source of visceral pain or discomfort, a source that is frequently difficult to identify. Main factors are stimuli originating from the gastro-intestinal tract, passing through the spinal cord and reaching several brain structures, including cortical and sub-cortical sites. It has been shown that some structures become thicker while others thinner as a result of lasting visceral pain, resulting in altered top-down effects on the visceral organs. Several hormones accompany these processes resulting in a complicated network activity. Recent research has revealed that IBS requires a complex approach, optimally provided by a therapeutic team of physicians, psychologist/psychiatrist, associates, and even the patient himself/herself. They may apply or suggest medicines, physiotherapy, lifestyle modifications, alimentary changes etc. An important feature is that the nocebo-effect plays an important role in the generation of IBS, thus one may think the opposite phenomenon, placebo-effect could be used in the therapeutic process. And really, placebo-analgesia is a method frequently used in the therapy of IBS. Placebo-analgesia affects brain processes, including pain processing, release of hormones, including endogenous opioids, the primary pain-decreasing factors. A top-down pain-modification system exists which can be affected and activated by the placebo-analgesia thus counteracting the nocebo-effects and improving the condition of the individual. The placebo phenomenon is interesting in itself, too. By now, the major question is not the existence of the placebo-effect but the mechanisms behind it. Recently, as brain-mapping techniques have gained their role in research, a lot of new information proves that the placebo-effect (as well as the nocebo-effect) is a complex phenomenon that involves several different brain sites, including the brain cortex and the limbic system, respectively.P The placebo-effect is widely used in clinical practice, first of all as a reference treatment when new drugs or medicines are tested for their effectivity. There are numerous ethical problems in this area, recently, for example, when testing Covid-19 vaccines. The main problem is whether it is legal to keep a non-treated population, whether the placebo-group should be treated immediately after the trial ends, whether the members of the placebo-group should get adequate information.

Evaluation of rheological performance of a local modified bitumen by Styrene Butadiene Styrene polymer used in wearing course

In road construction, bitumen is the binder that gathered the different aggregates of road pavements. Bitumen, as a viscoelastic material, influences considerably the rheological behavior of bitumen concrete. The bitumen used in Algeria, showed its limits face to the traffic, which is increasing continuously. This research aims to valorize SBS polymer in wearing course by modifying a pure 35/50 bitumen. The present paper aims to study the polymer derived from styrene and butadiene (SBS) from the company Kraton Polymers International Ltd in the modification of a bitumen to improve its mechanical characteristics.To this end, the incorporation of SBS polymer was carried out according to two contents: 5.0 and 7.5% (by weight of asphalt), the objective being to evaluate the influence of this type of polymer on the rheological properties of the bitumen ordinary road including viscosity and modulus.The results reveal that the bitumen modified with 7.5% of SBS has better mechanical performance on the rigidity and the elasticity compared to the conventional bitumen. Recommendations have been made to implement a bitumen modification system to improve its quality and therefore the durability of bituminous pavements in the south of Algeria.