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Magnetotactic bacteria (MTB) are a unique ecophysiological group of iron-metabolizing bacteria that have immense potential biotechnological applications. These bacteria have predominantly been isolated from oxygen-limited conditions of aquatic niches and rarely from the soils. The Western Ghats biodiversity hotspot has been well-studied for its fauna and flora diversity. The present study includes optimization of enrichment medium for cultivation of MTB, to suit aerobic mesophiles from forest soil. The major components included were Ferric quinate and Resazurin. The enrichment and isolates were characterized for their magnetic properties using magnetotaxis on agar plates, Vibrating Sampler Magnetometer (VSM), and X-ray diffraction (XRD) analysis. The isolates, namely Bacillus sp. S1 (MN212953), Sphingoaurantiacus sp. S2_03 (MN212954), Burkholderia sp. S2_08 (MN212955) and Microvirga sp. S2_09 (MN212956) were isolated and characterized to have a magnetosome size of 2.5–8 nm. Our study is the first report on the enrichment and isolation of MTB from Western Ghats forest soil. [ABSTRACT FROM AUTHOR]

Microorganisms produce a diverse group of biomolecules having amphipathic nature (amphiphiles). Microbial amphiphiles, including amyloids, bio-surfactants, and other exo-polymeric substances, play a crucial role in various biological processes and have gained significant attention recently. Although diverse in biochemical composition, these amphiphiles have been reported for common microbial traits like biofilm formation and pathogenicity due to their ability to act as surface active agents with active interfacial properties essential for microbes to grow in various niches. This enables microbes to reduce surface tension, emulsification, dispersion, and attachment at the interface. In this report, the ecological importance and biotechnological usage of important amphiphiles have been discussed. The low molecular weight amphiphiles like biosurfactants, siderophores, and peptides showing helical and antimicrobial activities have been extensively reported for their ability to work as quorum-sensing mediators. While high molecular weight amphiphiles make up amyloid fibers, exopolysaccharides, liposomes, or magnetosomes have been shown to have a significant influence in deciding microbial physiology and survival. In this report, we have discussed the functional similarities and biochemical variations of several amphipathic biomolecules produced by microbes, and the present report shows these amphiphiles showing polyphyletic and ecophysiological groups of microorganisms and hence can 'be replaced in biotechnological applications depending on the compatibility of the processes. [ABSTRACT FROM AUTHOR]

Nuclear export of mRNAs is a critical regulatory step in eukaryotic gene expression. The mRNA transcript undergoes extensive processing, and is loaded with a set of RNA-binding proteins (RBPs) to form export-competent messenger ribonucleoprotein particles (mRNPs) in the nucleus. During the transit of mRNPs through the nuclear pore complex (NPC), the DEAD-box ATPase - DDX19 (herein referring to DDX19A and DDX19B) - remodels mRNPs at the cytoplasmic side of the NPC, by removing a subset of RNA-binding proteins to terminate mRNP export. This requires the RNA-dependent ATPase activity of DDX19 and its dynamic interactions with Gle1 and Nup214. However, the regulatory mechanisms underlying these interactions are unclear. We find that DDX19 gets covalently attached with a small ubiquitin-like modifier (SUMO) at lysine 26, which enhances its interaction with Gle1. Furthermore, a SUMOylation-defective mutant of human DDX19B, K26R, failed to provide a complete rescue of the mRNA export defect caused by DDX19 depletion. Collectively, our results suggest that SUMOylation fine-tunes the function of DDX19 in mRNA export by regulating its interaction withGle1. This study identifies SUMOylation of DDX19 as a modulatory mechanism during the mRNA export process. [ABSTRACT FROM AUTHOR]

Thermostable glycoprotein amyloid bioemulsifier BE-AM1 was reported from Solibacillus silvestris AM1. S. silvestris could produce better BE-AM1 in 1% inoculum size and 18h inoculum age. The BE-AM1 production by S. silvestris AM1 has been seen to be unaffected by amending the production and growth medium (Zobel Marine medium) with Carbon and Nitrogen sources. The effects of 16 nutrient factors (from ZM medium) were analyzed statistically by one factor at a time, Plackett-Burman and Response surface methodologies. Among the nutritive factors, yeast extract and peptone were found to be significant, increasing the production quantity of BE-AM1. The time course of production of BE-AM1 was affected significantly by altering the release of the biomolecule from the surface of the bacterium. This will be the first study to analyse the effect of factors influencing the production of industrially important functional amyloid protein from bacterial source having potential in environmental remediation and microbial interaction. [ABSTRACT FROM AUTHOR]

Microbial amphiphiles play an important role in environmental activities such as microbial signaling, bioremediation, and biofilm formation. Microorganisms rely on their unique characteristics of interfaces to carry out critical biological functions, which are helped by amphipathic biomolecules known as amphiphiles. Bacillus amyloids aid in cell adhesion and biofilm formation. Pseudomonas sp. are essential in biofilm development and are a vital survival strategy for many bacteria. Furthermore, Pseudomonas and Bacillus are well-known for their ability to produce biosurfactants with a range of applications, including bioremediation and removing biological pollutants from different environments. The study employed 31 different media types and a range of analytical techniques to assess the presence of amyloid proteins and the absence of biosurfactants in Bacillus licheniformis K125 (GQ850525.1) and Pseudomonas fluorescens CHA0. The presence of amyloid proteins was confirmed through Congo red and thioflavin T staining. The carefully constructed medium also efficiently inhibited the synthesis of biosurfactants by these bacteria. Additionally, surface tension measurements, emulsification index, thin-layer chromatography, and high-performance thin-layer chromatography analyses indicated the absence of biosurfactants in the tested media. • Pseudomonas and Bacillus sp. produce amphiphiles like biosurfactants and amyloid. • The growth of amyloid and biosurfactants is influenced by nutritional triggers. • Nutrition affects the production of biosurfactant significantly. [ABSTRACT FROM AUTHOR]

Micro-RNA mediated suppression of mRNA translation represents a major regulatory mode of post-transcriptional gene expression. Recently, the nucleoporin Nup358 was shown to interact with AGO protein, a key component of miRNA-induced silencing complex (miRISC), and facilitate the coupling of miRISC with target mRNA. Previous results suggested that SUMO-interacting motifs (SIMs) present on Nup358 mediate interaction with AGO protein. Here we show that Nup358-SIM has multiple interacting regions on AGO2, specifically within the N, PAZ and MID domains, with an affinity comparable to SIM-SUMO1 interaction. The study also unraveled specific residues involved in the interaction of AGO2 with miRNA-loading components such as Dicer and HSP90. Collectively, the results support the conclusion that multiple SIMs contribute to the association of Nup358 with AGO2. • Nup358-SIM interacts with AGO2 N-, PAZ and MID domains. • In the full length context, N-domain of AGO2 is important for interaction with Nup358-SIM. • Binding of Nup358-SIM with AGO2 fragments and SUMO is of similar affinity range. • Human AGO2 residues L115 and V117 within N-domain contribute to interaction with HSP90. • Human AGO2 residues F491, Y494, L508 and Y512 within MID domain contribute to interaction with Dicer. [ABSTRACT FROM AUTHOR]

Dandruff is one of the most common clinically manifested and studied scalp disorders. It has been associated with both bacteria and fungi. Bacteria and fungi inhabiting the scalp are known to influence each other and manifestation of dandruff. Fungal and bacterial isolates from scalp epithelial flakes (dandruff) were identified by rDNA sequencing. Local oils were tested for fungal and bacterial inhibition, interaction and biofilm formation, cell–cell interactions were studied by auto aggregation and surface thermodynamics studies. The isolates Bacillus sp.C2b1 (MK036745) and Malassezia sp. C2y1 (MK036746) were inhibited by Mahabhrungraj oil. The fungal morphological switch was evident and dependent on nutrition. Cell aggregation studies suggested the interaction of bacteria with yeast (non-pathogenic) phase of the fungus. Bacterial and yeast cells were found to be compatible for biofilm formation. The fungal mycelial surfaces were found to be conducive for interaction with both bacterial cells and yeast forms. The results here indicate the significance of mycelial phase of scalp-isolated fungus in interaction with the bacterial surfaces and also with self-yeast phase surface. This is the first report of the interaction between scalp-isolated microorganisms with respect to their surface interaction capabilities. [ABSTRACT FROM AUTHOR]

Highlights: [•] Genus Solibacillus has been reported for the first time for bioemulsifier production. [•] This is the first report of flagellin-like glycoprotein bioemulsifier. [•] Bioemulsifier AM1 is thermostable, salt tolerant and active in wide pH range. [•] It is versatile in emulsifying aliphatic and aromatic hydrocarbons as well as oils. [•] Emulsions formed by it have pseudoplastic non-Newtonian rheological properties. [ABSTRACT FROM AUTHOR]

Abstract: Two in-line monitoring probes were inserted into a 3.2L batch cooling crystallizer to monitor the progression of a dextrose monohydrate crystallization and how it was influenced by process variables including impurities, seed size and initial dextrose concentration. The probes used were a K-patents refractometer and a Lasentec FBRM probe. These probes were applied to continuously monitor dextrose concentration in solution and crystal chord length distribution throughout the duration of the crystallization. The influence of process variables on crystallizer performance, as determined by final crystal yield and chord size, may not be intuitive and some unexpected results occurred. The continuous in-line measurement data proved very useful for interpreting how variations in the process variables influenced the crystallizer performance. Supersaturation is a key variable in the control of the crystallization process as it influences both nucleation and crystal growth. In-line monitoring of solution dextrose concentration can be applied to continuously evaluate supersaturation and this can then be applied to control supersaturation so as to achieve a desired crystallizer performance. [Copyright &y& Elsevier]

In this work, a seeded batch cooling crystallizer was used to study dextrose monohydrate crystallization using in situ techniques. Experiments were conducted to investigate the influence of cooling profile (natural, linear, and controlled cooling) and seed mass on dextrose monohydrate crystallization. Two in situ techniques, Lasentec focused beam reflectance measurement (FBRM) and an in-line process refractometer for monitoring aqueous crystallization of dextrose monohydrate, were used. The seed mass and cooling profile were focused on, in particular, determining the effect of secondary nucleation and crystal growth rate on the final crystal size distribution, the evolution of supersaturation, and yield of dextrose monohydrate. Experimental results were analyzed to evaluate the kinetic constants from growth and nucleation power law functions with supersaturation. The results showed that increasing the seed mass decreased the level and the peak of supersaturation and increased the crystal growth rate. The experiment performed with natural cooling and with high seed mass resulted in the highest yield. Furthermore, the results showed a significant increase in the final crystal size with decreasing seed mass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Provides information about green synthesis of industrial amphiphiles. • Enlists similarity in biosurfactant gene cassettes and biomolecules. • Biosurfactant roles and applications have been elucidated. Microbial surfactants are a large number of amphipathic biomolecules with a myriad of biomolecule constituents from various microbial sources that have been studied for their surface tension reduction activities. With unique properties, their applications have been increased in different areas including environment, medicine, healthcare, agriculture and industries. The present review aims to study the biochemistry and biosynthesis of biosurfactants exhibiting varying biomolecular structures which are produced by different microbial sources. It also provides details on roles played by biosurfactants in nature as well as their potential applications in various sectors. Basic biomolecule content of all the biosurfactants studied showed presence of carbohydrates, aminoacids, lipids and fattyacids. The data presented here would help in designing, synthesis and application of tailor-made novel biosurfactants. This would pave a way for perspectives of research on biosurfactants to overcome the existing bottlenecks in this field. [ABSTRACT FROM AUTHOR]