Mammalian brain plasma membranes : Isolation, enzymatic, and chemical characterization

Two variants of a simplified procedure for the isolation of plasma membrane fractions from monkey and rat brains, are described. The preparations show marked enrichments in the marker enzymes, (Na⁺-K⁺) adenosine triphosphatase, acetylcholinesterase, 5′-nucleotidase and adenylate cyclase. Lipid analysis and a protein electrophoretic pattern are presented. An enzymatic check has been made to assess for contamination by other cellular organelles. The amino acid composition of brain membrane proteins show a resemblance to the reported composition of erythrocyte ghost proteins but differ from myelin proteins.     

Arthrobacter pokkalii sp nov,a Novel Plant Associated Actinobacterium with Plant Beneficial Properties,Isolated from Saline Tolerant Pokkali Rice,Kerala, India

A novel yellow colony-forming bacterium, strain P3B162^T was isolated from the pokkali rice rhizosphere from Kerala, India, as part of a project study aimed at isolating plant growth beneficial rhizobacteria from saline tolerant pokkali rice and functionally evaluate their abilities to promote plant growth under saline conditions. The novel strain P3B162^T possesses plant growth beneficial traits such as positive growth on 1-aminocyclopropane-1-carboxylic acid (ACC), production of indole acetic acid (IAA) and siderophore. In addition, it also showed important phenotypic characters such as ability to form biofilm and utilization of various components of plant root exudates (sugars, amino acids and organic acids), clearly indicating its lifestyle as a plant rhizosphere associated bacterium. Taxonomically, the novel strain P3B162^T was affiliated to the genus Arthrobacter based on the collective results of phenotypic, genotypic and chemotaxonomic analyses. Moreover, molecular analysis using 16S rRNA gene showed Arthrobacter globiformis NBRC 12137^T, Arthrobacter pascens DSM 20545^T and Arthrobacter liuii DSXY973^T as the closely related phylogenetic neighbours, showing more than 98% 16S rRNA similarity values, whereas the recA gene analysis displayed Arthrobacter liuii JCM 19864^T as the nearest neighbour with 94.7% sequence similarity and only 91.7% to Arthrobacter globiformis LMG 3813^T and 88.7% to Arthrobacter pascens LMG 16255^T. However, the DNA-DNA hybridization values between strain P3B162^T, Arthrobacter globiformis LMG 3813^T, Arthrobacter pascens LMG 16255^T and Arthrobacter liuii JCM 19864^T was below 50%. In addition, the novel strain P3B162^T can be distinguished from its closely related type strains by several phenotypic characters such as colony pigment, tolerance to NaCl, motility, reduction of nitrate, hydrolysis of DNA, acid from sucrose, cell wall sugars and cell wall peptidoglycan structure. In conclusion, the combined results of this study support the classification of strain P3B162^T as a novel Arthrobacter species and we propose Arthrobacter pokkalii sp.nov.as its name. The type strain is P3B162^T (= KCTC 29498^T = MTCC 12358^T).     

Purification and properties of cis-aconitic decarboxylase

Summary Lyophilized and stored in a deep-freeze, the mycelial material was found to retain cis-aconitic decarboxylase activity unimpaired at the end of 2 months. Mycelia could be stored also in the frozen condition but after squeezing hard to remove as much of adherent water as possible. Extracts with maximum cis-aconitic decarboxylase activity were obtained when the frozen or better the lyophilized mycelia of Aspergillus terreus were ground in a mortar with phosphate buffer using pyrex glass powder as abrasive. Cis-aconitic decarboxylase was purified 25-fold by fractionation with ammonium sulfate, starting from extracts of the mycelia in phosphate buffer. The purified enzyme was considerably more stable than the crude extracts to storage and dialysis. The optimum pH was 5.8 using 0.2 m phosphate buffer; Km value was 5×10^-3 m at pH 5.8 and 37°C. EDTA and 8-hydroxyquinoline activated the enzyme; all metals tested inhibited the enzyme, Zn⁺⁺ and Cu⁺⁺ leading to complete inactivation. Fluoride, arsenite and azide also inhibited the enzyme activity.     

Mixed company: a framework for understanding the composition and organization of mixed‐species animal groups

Mixed‐species animal groups (MSGs) are widely acknowledged to increase predator avoidance and foraging efficiency, among other benefits, and thereby increase participants' fitness. Diversity in MSG composition ranges from two to 70 species of very similar or completely different phenotypes. Yet consistency in organization is also observable in that one or a few species usually have disproportionate importance for MSG formation and/or maintenance. We propose a two‐dimensional framework for understanding this diversity and consistency, concentrating on the types of interactions possible between two individuals, usually of different species. One axis represents the similarity of benefit types traded between the individuals, while the second axis expresses asymmetry in the relative amount of benefits/costs accrued. Considering benefit types, one extreme represents the case of single‐species groups wherein all individuals obtain the same supplementary, group‐size‐related benefits, and the other extreme comprises associations of very different, but complementary species (e.g. one partner creates access to food while the other provides vigilance). The relevance of social information and the matching of activities (e.g. speed of movement) are highest for relationships on the supplementary side of this axis, but so is competition; relationships between species will occur at points along this gradient where the benefits outweigh the costs. Considering benefit amounts given or received, extreme asymmetry occurs when one species is exclusively a benefit provider and the other a benefit user. Within this parameter space, some MSG systems are constrained to one kind of interaction, such as shoals of fish of similar species or leader–follower interactions in fish and other taxa. Other MSGs, such as terrestrial bird flocks, can simultaneously include a variety of supplementary and complementary interactions. We review the benefits that species obtain across the diversity of MSG types, and argue that the degree and nature of asymmetry between benefit providers and users should be measured and not just assumed. We then discuss evolutionary shifts in MSG types, focusing on drivers towards similarity in group composition, and selection on benefit providers to enhance the benefits they can receive from other species. Finally, we conclude by considering how individual and collective behaviour in MSGs may influence both the structure and processes of communities.     

An In Silico Evaluation of Molecular Interaction Between Antimicrobial Peptide Subtilosin A of Bacillus subtilis with Virulent Proteins of Aeromonas hydrophila

International Journal of Peptide Research and Therapeutics - Subtilosin A, a cyclic peptide from Bacillus subtilis is known for its antimicrobial activity against a diverse range of bacteria....     

A Brain-Computer Interface Based Cognitive Training System for Healthy Elderly: A Randomized Control Pilot Study for Usability and Preliminary Efficacy

Cognitive decline in aging is a pressing issue associated with significant healthcare costs and deterioration in quality of life. Previously, we reported the successful use of a novel brain-computer interface (BCI) training system in improving symptoms of attention deficit hyperactivity disorder. Here, we examine the feasibility of the BCI system with a new game that incorporates memory training in improving memory and attention in a pilot sample of healthy elderly. This study investigates the safety, usability and acceptability of our BCI system to elderly, and obtains an efficacy estimate to warrant a phase III trial. Thirty-one healthy elderly were randomized into intervention (n = 15) and waitlist control arms (n = 16). Intervention consisted of an 8-week training comprising 24 half-hour sessions. A usability and acceptability questionnaire was administered at the end of training. Safety was investigated by querying users about adverse events after every session. Efficacy of the system was measured by the change of total score from the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) before and after training. Feedback on the usability and acceptability questionnaire was positive. No adverse events were reported for all participants across all sessions. Though the median difference in the RBANS change scores between arms was not statistically significant, an effect size of 0.6SD was obtained, which reflects potential clinical utility according to Simon’s randomized phase II trial design. Pooled data from both arms also showed that the median change in total scores pre and post-training was statistically significant (Mdn = 4.0; p<0.001). Specifically, there were significant improvements in immediate memory (p = 0.038), visuospatial/constructional (p = 0.014), attention (p = 0.039), and delayed memory (p<0.001) scores. Our BCI-based system shows promise in improving memory and attention in healthy elderly, and appears to be safe, user-friendly and acceptable to senior users. Given the efficacy signal, a phase III trial is warranted.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01661894","term_id":"NCT01661894"}}NCT01661894     

Methodologies to decipher the cell secretome

The cell secretome is a collection of proteins consisting of transmembrane proteins (TM) and proteins secreted by cells into the extracellular space. A significant portion (~ 13–20%) of the human proteome consists of secretory proteins. The secretory proteins play important roles in cell migration, cell signaling and communication. There is a plethora of methodologies available like Serial Analysis of Gene Expression (SAGE), DNA microarrays, antibody arrays and bead-based arrays, mass spectrometry, RNA sequencing and yeast, bacterial and mammalian secretion traps to identify the cell secretomes. There are many advantages and disadvantages in using any of the above methods. This review aims to discuss the methodologies available along with their potential advantages and disadvantages to identify secretory proteins. This review is a part of a Special issue on The Secretome. This article is part of a Special Issue entitled: An Updated Secretome.     

The study of genetic diversity patterns of Coffea commersoniana, an endangered coffee species from Madagascar: a model for conservation of other littoral forest species

Madagascar has 59 described species of Coffea, of which 42 are listed as critically endangered, endangered, or vulnerable by the criteria of the Red List Category system of the World Conservation Union (IUCN). The littoral forest of Madagascar is a distinctive type of humid evergreen forest restricted to unconsolidated sand located within a few kilometers of the Indian Ocean, now persisting only as small fragments with ca. 10 % of its original range remaining. In an attempt to understand the genetic diversity of Madagascan coffee species, we studied ex situ and in situ populations of Coffea commersoniana, an endemic species of the littoral forests of southeastern Madagascar and soon to be impacted by mining activities in that region. The in situ populations studied showed higher genetic diversity than the ex situ population. The genetic partitioning among the two in situ populations of C. commersoniana was high enough to necessitate keeping the two populations separate for restoration purposes. Based on these findings, recommendations for conservation management (in situ and ex situ) are made.     

Cross-Species Array Comparative Genomic Hybridization Identifies Novel Oncogenic Events in Zebrafish and Human Embryonal Rhabdomyosarcoma

Human cancer genomes are highly complex, making it challenging to identify specific drivers of cancer growth, progression, and tumor maintenance. To bypass this obstacle, we have applied array comparative genomic hybridization (array CGH) to zebrafish embryonal rhabdomyosaroma (ERMS) and utilized cross-species comparison to rapidly identify genomic copy number aberrations and novel candidate oncogenes in human disease. Zebrafish ERMS contain small, focal regions of low-copy amplification. These same regions were commonly amplified in human disease. For example, 16 of 19 chromosomal gains identified in zebrafish ERMS also exhibited focal, low-copy gains in human disease. Genes found in amplified genomic regions were assessed for functional roles in promoting continued tumor growth in human and zebrafish ERMS – identifying critical genes associated with tumor maintenance. Knockdown studies identified important roles for Cyclin D2 (CCND2), Homeobox Protein C6 (HOXC6) and PlexinA1 (PLXNA1) in human ERMS cell proliferation. PLXNA1 knockdown also enhanced differentiation, reduced migration, and altered anchorage-independent growth. By contrast, chemical inhibition of vascular endothelial growth factor (VEGF) signaling reduced angiogenesis and tumor size in ERMS-bearing zebrafish. Importantly, VEGFA expression correlated with poor clinical outcome in patients with ERMS, implicating inhibitors of the VEGF pathway as a promising therapy for improving patient survival. Our results demonstrate the utility of array CGH and cross-species comparisons to identify candidate oncogenes essential for the pathogenesis of human cancer.