Isolation, screening of Aspergillus flavus and its production parameters for á- amylase under solid state fermentation

The amylase producing fungi were isolated from spoiled fruits, vegetables and soil, in and around Bangalore, Karnataka, India. The isolates were identified and five fungal species were screened. The best amylase producer among them, Aspergillus sp was selected for enzyme production by both sub merged fermentation using mineral salt medium (MSM) and solid state fermentations using wheat bran as a solid substrate. The various parameters influencing solid state fermentation were optimized. The most important factors are such as pH, incubation temperature, incubation period, carbon sources, nitrogen sources and moisture content. The maximum amount of enzyme production was obtained when solid state fermentation was carried out with soluble starch as carbon source and beef extract (1% each) as nitrogen source, optimum conditions of pH 7.0, an incubation temperature of 25 (±2) °C, incubation time 96 h and 62% moisture content

A preliminary pharmacognostical study on leaves and flowers of Michelia champaca L. Magnoliaceae

The present investigation was conducted to establish pharmacognostical profile for the leaves and flowers of Michelia champaca L. (Magnoliaceae) in order to establish its complete profile to aid in its identification and avoid confusion in taxonomic level for different species of the same genus. The study included macroscopical, organoleptical, microscopical and preliminary phytochemical analysis of the leaves and flowers. The study of the organoleptical evaluation revealed the presence of colour, odour and texture. The microscopic analysis showed thedifferences in cell structures, arrangement and shape of leaves and flowers. The physical characters of various solvent extracts showed the presence of colour, odour and consistency of the powdered leaves and flowers. Finally, the preliminary phytochemical analysis confirmed for the presence of alkaloids, saponins, tannins, glycosides, carbohydrates, amino acid, flavonoids and sterols in both leaves and flowers. The present findings may be used to establish the authenticity of leaves and flowers of Michelia champaca L. for their proper identification and standardization in order to collect raw plants for the preparation of herbal drugs

Stable kinetochore–microtubule interactions depend on the Ska complex and its new component Ska3/C13Orf3

Ska1 and Ska2 form a complex at the kinetochore–microtubule (KT–MT) interface and are required for timely progression from metaphase to anaphase. Here, we use mass spectrometry to search for additional components of the Ska complex. We identify C13Orf3 (now termed Ska3) as a novel member of this complex and map the interaction domains among the three known components. Ska3 displays similar characteristics as Ska1 and Ska2: it localizes to the spindle and KT throughout mitosis and its depletion markedly delays anaphase transition. Interestingly, a more complete removal of the Ska complex by concomitant depletion of Ska1 and Ska3 results in a chromosome congression failure followed by cell death. This severe phenotype reflects a destabilization of KT–MT interactions, as demonstrated by reduced cold stability of KT fibres. Yet, the depletion of the Ska complex only marginally impairs KT localization of the KMN network responsible for MT attachment. We propose that the Ska complex functionally complements the KMN, providing an additional layer of stability to KT–MT attachment and possibly signalling completion of attachment to the spindle checkpoint

Structural plasticity of peanut lectin: an X-ray analysis involving variation in pH, ligand binding and crystal structure

Until recently, it has only been possible to grow crystals of peanut lectin when complexed with sugar ligands. It is now shown that it is possible to grow peanut lectin crystals at acidic pH in the presence of oligopeptides corresponding to a loop in the lectin molecule. Crystals have also been prepared in the presence of these peptides as well as lactose. Low-pH crystal forms of the lectin-lactose complex similar to those obtained at neutral pH have also been grown. Thus, crystals of peanut lectin grown under different environmental conditions, at two pH values with and without sugar bound to the lectin, are now available. They have been used to explore the plasticity and hydration of the molecule. A detailed comparison between different structures shows that the lectin molecule is sturdy and that the effect of changes in pH, ligand binding and environment on it is small. The region involving the curved front β-sheet and the loops around the second hydrophobic core is comparatively rigid. The back β-sheet involved in quaternary association, which exhibits considerable variability, is substantially flexible, as is the sugar-binding region. The numbers of invariant water molecules in the hydration shell are small and they are mainly involved in metal coordination or in stabilizing unusual structural features. Small consistent movements occur in the combining site upon sugar binding, although the site is essentially preformed

Glycotope structures and intramolecular affinity factors of plant lectins for Tn/T antigens

B

Design and synthesis of novel quercetin metal complexes as IL-6 inhibitors for anti-inflammatory effect in SARS-CoV-2

One of the most common causes of mortality in COVID-19 patients is cytokine release syndrome (CRS). Though several cytokines are involved in CRS, the role of Interleukin 6 is significant. Considering the importance of IL-6 inhibition and the drawbacks of the existing monoclonal antibodies, the present study develops new flavonoid metal complexes as immune boosters targeting IL-6 for SARS-CoV-2 treatment. To identify the potential flavonoids from 152 secondary plant metabolites, PyRx 0.9 tool has been used. The top scorer quercetin was converted into quercetin-oxime. Seven metal complexes (QM-1 to QM-7) were made from quercetin-oxime by utilizing divalent metals such as zinc, copper, magnesium, cobalt, barium, and cadmium. It was assumed that all compounds were moderately soluble and would not penetrate the BBB through in silico ADME studies. However, the in vitro heamolytic research revealed a modest heamolytic effect in all seven complexes. To know the IL-6 inhibitory potential preliminary level, the complexes were screened for cytotoxicity in cell lines MCF-7 which predominantly expresses the IL-6 level. The cytotoxic effects of all complexes were considerable relative to the marketable Nutridac formulation. The complexes quercetin-Zinc (QM1) and quercetin-Zinc-Ascorbic acid (QM7) showed significant cytotoxicity on MCF-7 compared to Nutridac and no cytotoxic toward the normal cell lines

Analysis of the functional repertoire of a mutant form of survivin, K129E, which has been linked to lung cancer

Background Survivin is a protein that is normally present only in G2 and M-phases in somatic cells, however, in cancer cells, it is expressed throughout the cell cycle. A prosurvival factor, survivin is both an inhibitor of apoptosis and an essential mitotic protein, thus it has attracted much attention as a target for new oncotherapies. Despite its prevalence in cancer, reports of survivin mutations have mostly been restricted to loci within its promoter, which increase the abundance of the protein. To date the only published mutation within the coding sequence is an adenine > guanine substitution in exon 4. This polymorphism, which was found in a cohort of Korean lung cancer patients, causes a lysine > glutamic acid mutation (K129E) in the protein. However, whether it plays a causative role in cancer has not been addressed. Methods Using site directed mutagenesis we recapitulate K129E expression in cultured human cells and assess its anti-apoptotic and mitotic activities. Results K129E retains its anti-apoptotic activity, but causes errors in mitosis and cytokinesis, which may be linked to its reduced affinity for borealin. Conclusion K129E expression can induce genomic instability by introducing mitotic aberrations, thus it may play a causative role in cancer

Allele Intersection Analysis: A Novel Tool for Multi Locus Sequence Assignment in Multiply Infected Hosts

Wolbachia are wide-spread, endogenous α-Proteobacteria of arthropods and filarial nematodes. 15–75% of all insect species are infected with these endosymbionts that alter their host's reproduction to facilitate their spread. In recent years, many insect species infected with multiple Wolbachia strains have been identified. As the endosymbionts are not cultivable outside living cells, strain typing relies on molecular methods. A Multi Locus Sequence Typing (MLST) system was established for standardizing Wolbachia strain identification. However, MLST requires hosts to harbour individual and not multiple strains of supergroups without recombination. This study revisits the applicability of the current MLST protocols and introduces Allele Intersection Analysis (AIA) as a novel approach. AIA utilizes natural variations in infection patterns and allows correct strain assignment of MLST alleles in multiply infected host species without the need of artificial strain segregation. AIA identifies pairs of multiply infected individuals that share Wolbachia and differ in only one strain. In such pairs, the shared MLST sequences can be used to assign alleles to distinct strains. Furthermore, AIA is a powerful tool to detect recombination events. The underlying principle of AIA may easily be adopted for MLST approaches in other uncultivable bacterial genera that occur as multiple strain infections and the concept may find application in metagenomic high-throughput parallel sequencing projects