A purine permease in Candida glabrata

Abstract Competition experiments revealed that adenine and guanine were transported by a purine permease in both Candida glabrata 4 and a C. glabrata 4 cytosine permease negative mutant. The C. glabrata 4 cytosine permease negative mutant was isolated using 5-fluorocytosine selection. This mutant no longer transported cytosine, but transported adenine and guanine. A transport system for hypoxanthine was not detected. Hence, in addition to the cytosine permease, a purine permease exists in C. glabrata . This differs from the purine cytosine permeases in Saccharomyces cereuisiae and Candida albicans which transport adenine, cytosine, guanine and hypoxanthine.     

Gene Specific Impedimetric Bacterial DNA Sensor for Rheumatic Heart Disease

An impedimetric mga gene specific DNA sensor was developed by immobilization of single stranded DNA probe onto the screen printed modified gold-dendrimer nanohybrid composite electrode for early and rapid detection of S. pyogenes in human throat swab samples causing rheumatic heart disease. Electrochemical impedance response was measured after hybridization with bacterial single stranded genomic DNA (ssG-DNA) with probe. The sensor was found highly specific to S. pyogenes and can detect as low as 0.01 ng ssDNA in 6 µL sample only in 30 min. The nanohybrid sensor was also tested with non-specific pathogens and characterized by FTIR. An early detection of the pathogen S. pyogenes in human can save damage of mitral and aortic heart valves (rheumatic heart disease) by proper medical care.     

Reconstitution of denatured E. coli alkaline phosphatase with E. coli ribosome.

E. coli alkaline phosphatase was denatured by physical/chemical means. In vitro reconstitution of this denatured enzyme was assisted by 70S E. coli ribosome, as shown by the recovery of its catalytic competence. Almost total recovery of activity of the totally inactivated enzyme was obtained in presence of equimolar concentration of 70S ribosome at 50 degrees C.     

Hyaluronic acid engrafted metformin loaded graphene oxide nanoparticle as CD44 targeted anti-cancer therapy for triple negative breast cancer

BackgroundTriple negative breast cancer (TNBC) is the most aggressive form of breast cancer with limited treatment modalities. It is associated with high propensity of cancer recurrence.MethodsUV Spectroscopy, FTIR, DLS, Zeta potential, TEM and SEM were employed to characterize nanoparticles. MTT assay, Wound healing assay, SEM, Immunocytochemistry analysis, Western blot, RT-PCR, mammosphere formation assay were employed to study apoptosis, cell migration and stemness. Tumor regression was studied in chick embryo xenograft and BALB/c mice model.ResultsHylaluronic acid engrafted metformin loaded graphene oxide (HA-GO-Met) nanoparticles exhibited an anti-cancer efficacy at much lower dosage as compared to metformin alone. HA-GO-Met nanoparticles induced apoptosis and inhibited cell migration of TNBC cells by targeting miR-10b/PTEN axis via NFkB-p65. Upregulation of PTEN affected pAKT(473) expression that induced apoptosis. Cell migration was inhibited by reduction of pFAK/integrinβ1 expressions. Treatment inhibited epithelial mesenchymal transition (EMT) and reduced stemness as evident from the increase in E-cadherin expression, inhibition of mammosphere formation and low expression levels of stemness markers including nanog, oct4 and sox2 as compared to control. Moreover, tumor regression was studied in chick embryo xenograft and BALB/c mice model. HA-GO-Met nanoparticle treatment reduced tumor load and nullified toxicity in peripheral organs imparted by tumor.ConclusionsHA-GO-Met nanoparticles exhibited an enormous anti-cancer efficacy in TNBC in vitro and in vivo.General significanceHA-GO-Met nanoparticles induced apoptosis and attenuated cell migration in TNBC. It nullified overall toxicity imparted by tumor load. It inhibited EMT and reduced stemness and thereby addressed the issue of cancer recurrence.     

Liposome-mediated cytosolic delivery of macromolecules and its possible use in vaccine development.

In the majority of bacterial and viral infections the generation of cytotoxic T cells is of particular interest because such pathogens are able to escape the host defence mechanisms by surviving intracellularly within the phagocytic cells. To generate a CD8+ T lymphocyte response against exogenous antigens, the prerequisite is their delivery into the cytosol followed by processing and presentation along with class I major histocompatibility complex (MHC-I) molecules. In the present study we describe the method of liposome-based delivery of antigens and other macromolecules into the cytosol of target cells. To develop safe and effective methods for generating CD8+ T lymphocytes, we exploited the fusogenic character of lipids derived from lower organisms, that is baker's yeast (Saccharomyces cerevisiae). The degree of fusion with model membrane systems using yeast lipid liposomes varied from 40-70%, as opposed to 1-8% observed with egg PtdCho liposomes, depending on the assay system used. The fusion of yeast lipid liposomes with macrophages resulted in effective delivery of the entrapped solutes into the cytoplasmic compartment. This was further supported by the inhibition of cellular protein synthesis in J774 A1 cells by ricin A, encapsulated in the yeast lipid liposomes. Interestingly, the model antigen ovalbumin, when entrapped in the yeast lipid liposomes, successfully elicited antigen reactive CD8+ T cell responses. It may be concluded that the liposomes made of lipids derived from S. cerevisiae can spontaneously fuse with macrophages, delivering a significant portion of their contents into the cytoplasmic compartment of the cells.