Characterization of xylanase from microbulbifer sp. CL37 for industrial applications

Xylan is the most abundant sugar in hemicellulose and can be found in plant biomass. Xylanase produced by microorganisms such as bacteria can be used in industries such as paper and pulp for deinking process. A halophilic bacterium, Microbulbifer sp. strain CL37, was previously isolated from mangrove sediment and its extracellular xylanase was characterized in this study. Strain CL37 is a motile Gram-negative bacterium with rod shape, catalase, and oxidase positive. Strain CL37 also can hydrolyse xylan, casein, gelatin, Tween 20, Tween 40, Tween 60 and Tween 80. Cells are sensitive to gentamicin, tetracycline, polymyxin B, doxycycline, minocycline and rifampicin. The xylanase exhibited maximum activity at 70°C, pH7, and absent of NaCl. The xylanase remained activity up to 14% (w/v) NaCl indicates it is halotolerant xylanase. The xylanase activity was enhanced in the presence of Al3+, Ca2+, Co2+, Cu+, Cu2+, Fe2+, Fe3+, Mn2+, and Zn2+ (112-175% relative activity), stable in K+, Na+, and Ni2+ (>80% relative activity), but reduced in the presence of Mg2+ (59% relative activity). The xylanase activity also enhanced in the presence of acetone (127% relative activity) and remains stable (>70% relative activity) in most of the tested detergent constituents. Xylanase is also compatible with commercial detergents such as Top®, Dynamo®, Sunlight®, Glo®, Breeze® and Dixan®. Evaluation of the enzymatic deinking activity demonstrated that xylanase from strain CL37 has the ability to detach the adsorbed ink particle from the surface of paper. Collectively, xylanase from Microbulbifer sp. strain CL37 could have potential in various applications, such as detergent formulation, lignocellulolytic biofuel production and paper deinking

Revealing the potential of xylanase from a new halophilic microbulbifer sp. CL37 with paper de-inking ability

Paper de-inking is one of the critical processes in pulp and paper industry as it is ecofriendly and energy saving. This process requires microbial enzymes such as xylanases with ability to withstand harsh bioprocess conditions. Microbulbifer is a halophilic genus with ability to produce hydrolytic enzymes that could be applied in the biotechnological industry. So far, none of the xylanases from this genus have been studied, particularly in paper de-inking process. Therefore, in this study, the xylanase of a new halophilic bacterium, Microbulbifer sp. strain CL37, was characterized. Strain CL37 produced maximum amount of xylanase at 14th hour of incubation at 30 °C. The xylanase demonstrated optimal activity at 70 °C and pH 7. The xylanase was stable at wide range of NaCl (0–14%, w/v), in the presence of Al3+, Ca2+, Co2+, Cu+, Cu2+, Fe2+, Fe3+, Mn2+, Zn2+, acetone, chloroform, ethanol, sodium deoxycholate, Triton X-100, Tween 20, 40, 60, and 80, indicating that it is a halotolerant enzyme with high stability in various additives. The xylanase also demonstrated its ability to de-ink paper with considerably high efficiency (159%) as compared to other strains. The valuable characteristics possessed by xylanase of strain CL37 could potentially benefit to de-inking process in paper industry

The association between epstein-barr virus (EBV) past infection with the risk of oral squamous cell carcinoma (OSCC)

The association of Epstein-Barr virus (EBV) with oral cancer has been widely reported in the past. However, previous studies mainly focused on the current infection of EBV without acknowledging the possibility of past infection in patients which may lead to oral cancer development. The present study aims to investigate the correlation between past EBV infections with Oral Squamous Cell Carcinoma (OSCC). Both Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibodies against EBV were screened to detect the presence of EBV in sera of OSCC patients using Enzyme-Linked Immunosorbent Assay (ELISA). The use of IgM antibody against EBV confirms current infection in patients, whereas IgG antibody would predict past infection throughout patients’ lifetime. Through the present study, we would be able to confirm whether patients with past EBV infection have a significant risk in developing oral cancer. ELISA tests were carried out to detect the presence of EBV IgG and IgM in 206 OSCC and control serum samples. Statistical analysis was performed using SPSS 12.0.1. Our results had shown that 96.6% (n = 199) of OSCC samples and 97.2% (n = 130) control were positive with EBV VCA IgG, however, none of the OSCC and control samples was positive for EBV VCA IgM. The presence of EBV VCA IgG in both OSCC and control suggest that past EBV infection does not play a significant role as a risk indicator for OSCC. Therefore, the association between EBV and OSCC was not well demonstrated in this study

The association between epstein-barr virus (EBV) past infection with the risk of oral squamous cell carcinoma (OSCC)

The association of Epstein-Barr virus (EBV) with oral cancer has been widely reported in the past. However, previous studies mainly focused on the current infection of EBV without acknowledging the possibility of past infection in patients which may lead to oral cancer development. The present study aims to investigate the correlation between past EBV infections with Oral Squamous Cell Carcinoma (OSCC). Both Immunoglobulin M (IgM) and Immunoglobulin G (IgG) antibodies against EBV were screened to detect the presence of EBV in sera of OSCC patients using Enzyme-Linked Immunosorbent Assay (ELISA). The use of IgM antibody against EBV confirms current infection in patients, whereas IgG antibody would predict past infection throughout patients’ lifetime. Through the present study, we would be able to confirm whether patients with past EBV infection have a significant risk in developing oral cancer. ELISA tests were carried out to detect the presence of EBV IgG and IgM in 206 OSCC and control serum samples. Statistical analysis was performed using SPSS 12.0.1. Our results had shown that 96.6% (n = 199) of OSCC samples and 97.2% (n = 130) control were positive with EBV VCA IgG, however, none of the OSCC and control samples was positive for EBV VCA IgM. The presence of EBV VCA IgG in both OSCC and control suggest that past EBV infection does not play a significant role as a risk indicator for OSCC. Therefore, the association between EBV and OSCC was not well demonstrated in this study

Genome-Wide Association Study of Treatment Refractory Schizophrenia in Han Chinese

We report the first genome-wide association study of a joint analysis using 795 Han Chinese individuals with treatment-refractory schizophrenia (TRS) and 806 controls. Three loci showed suggestive significant association with TRS were identified. These loci include: rs10218843 (P = 3.04×10−7) and rs11265461 (P = 1.94×10−7) are adjacent to signaling lymphocytic activation molecule family member 1 (SLAMF1); rs4699030 (P = 1.94×10−6) and rs230529 (P = 1.74×10−7) are located in the gene nuclear factor of kappa light polypeptide gene enhancer in B-cells 1 (NFKB1); and rs13049286 (P = 3.05×10−5) and rs3827219 (P = 1.66×10−5) fall in receptor-interacting serine/threonine-protein kinase 4 (RIPK4). One isolated single nucleotide polymorphism (SNP), rs739617 (P = 3.87×10−5) was also identified to be associated with TRS. The -94delATTG allele (rs28362691) located in the promoter region of NFKB1 was identified by resequencing and was found to associate with TRS (P = 4.85×10−6). The promoter assay demonstrated that the -94delATTG allele had a significant lower promoter activity than the -94insATTG allele in the SH-SY5Y cells. This study suggests that rs28362691 in NFKB1 might be involved in the development of TRS

Sequencing and Comparative Genome Analysis of Two Pathogenic Streptococcus gallolyticus Subspecies: Genome Plasticity, Adaptation and Virulence

Streptococcus gallolyticus infections in humans are often associated with bacteremia, infective endocarditis and colon cancers. The disease manifestations are different depending on the subspecies of S. gallolyticus causing the infection. Here, we present the complete genomes of S. gallolyticus ATCC 43143 (biotype I) and S. pasteurianus ATCC 43144 (biotype II.2). The genomic differences between the two biotypes were characterized with comparative genomic analyses. The chromosome of ATCC 43143 and ATCC 43144 are 2,36 and 2,10 Mb in length and encode 2246 and 1869 CDS respectively. The organization and genomic contents of both genomes were most similar to the recently published S. gallolyticus UCN34, where 2073 (92%) and 1607 (86%) of the ATCC 43143 and ATCC 43144 CDS were conserved in UCN34 respectively. There are around 600 CDS conserved in all Streptococcus genomes, indicating the Streptococcus genus has a small core-genome (constitute around 30% of total CDS) and substantial evolutionary plasticity. We identified eight and five regions of genome plasticity in ATCC 43143 and ATCC 43144 respectively. Within these regions, several proteins were recognized to contribute to the fitness and virulence of each of the two subspecies. We have also predicted putative cell-surface associated proteins that could play a role in adherence to host tissues, leading to persistent infections causing sub-acute and chronic diseases in humans. This study showed evidence that the S. gallolyticus still possesses genes making it suitable in a rumen environment, whereas the ability for S. pasteurianus to live in rumen is reduced. The genome heterogeneity and genetic diversity among the two biotypes, especially membrane and lipoproteins, most likely contribute to the differences in the pathogenesis of the two S. gallolyticus biotypes and the type of disease an infected patient eventually develops

Role of X11 and ubiquilin as In Vivo Regulators of the Amyloid Precursor Protein in Drosophila

The Amyloid Precursor Protein (APP) undergoes sequential proteolytic cleavages through the action of β- and γ-secretase, which result in the generation of toxic β-amyloid (Aβ) peptides and a C-terminal fragment consisting of the intracellular domain of APP (AICD). Mutations leading to increased APP levels or alterations in APP cleavage cause familial Alzheimer's disease (AD). Thus, identification of factors that regulate APP steady state levels and/or APP cleavage by γ-secretase is likely to provide insight into AD pathogenesis. Here, using transgenic flies that act as reporters for endogenous γ-secretase activity and/or APP levels (GAMAREP), and for the APP intracellular domain (AICDREP), we identified mutations in X11L and ubiquilin (ubqn) as genetic modifiers of APP. Human homologs of both X11L (X11/Mint) and Ubqn (UBQLN1) have been implicated in AD pathogenesis. In contrast to previous reports, we show that overexpression of X11L or human X11 does not alter γ-secretase cleavage of APP or Notch, another γ-secretase substrate. Instead, expression of either X11L or human X11 regulates APP at the level of the AICD, and this activity requires the phosphotyrosine binding (PTB) domain of X11. In contrast, Ubqn regulates the levels of APP: loss of ubqn function leads to a decrease in the steady state levels of APP, while increased ubqn expression results in an increase in APP levels. Ubqn physically binds to APP, an interaction that depends on its ubiquitin-associated (UBA) domain, suggesting that direct physical interactions may underlie Ubqn-dependent regulation of APP. Together, our studies identify X11L and Ubqn as in vivo regulators of APP. Since increased expression of X11 attenuates Aβ production and/or secretion in APP transgenic mice, but does not act on γ-secretase directly, X11 may represent an attractive therapeutic target for AD