Innovation in the food industry using microbial transglutaminase: Keys to success and future prospects.

Transglutaminase (TG) catalyzes cross-linking between the γ-carboxyamide groups of glutamine residues and the ε-amino groups of lysine residues in polypeptide chains, yielding ε- (γ-glutamyl) lysine (G-L) bonds. By forming a network structure in the protein via G-L bonds, it is possible to increase the viscosity of protein solutions or to cause gelation. Nearly thirty years have passed since microbial TG (MTG) appeared in the food enzyme market.

Screening of microorganisms producing a novel protein-asparaginase and characterization of the enzyme derived from Luteimicrobium album.

A screening system using enrichment culture has been established with the aim of obtaining a novel enzyme for protein modification that has not been previously reported. This enzyme catalyzes deamidation of the side-chain amide group of asparagine in proteins. Enrichment culture of 390 soil samples was carried out with Z-Asn-Gly as the sole source of nitrogen, and the reaction product, Z-Asp-Gly, was detected in the culture supernatant of 102 strains.

The β-catenin signaling pathway induces aggressive potential in breast cancer by up-regulating the chemokine CCL5.

β-Catenin signaling plays a pivotal role in the genesis of a variety of malignant tumors, but its role in breast cancer has not been fully elucidated. Here, we examined whether deregulation of β-catenin signaling is related to the aggressive characteristics of certain types of breast cancers. Analysis of cytokine levels in MDA-MB-231 cells overexpressing a constitutively active form of β-catenin (CAβ-catenin) revealed a higher level of CCL5 expression.

Increased oxidative stress in AOA3 cells disturbs ATM-dependent DNA damage responses.

Ataxia telangiectasia (AT) is caused by a mutation in the ataxia-telangiectasia-mutated (ATM) gene; the condition is associated with hyper-radiosensitivity, abnormal cell-cycle checkpoints, and genomic instability. AT patients also show cerebellar ataxia, possibly due to reactive oxygen species (ROS) sensitivity in neural cells. The ATM protein is a key regulator of the DNA damage response.

Effect of enzymatic deamidation on the heat-induced conformational changes in whey protein isolate and its relation to gel properties.

The effect of protein-glutaminase (PG) on the heat-induced conformational changes in whey protein isolate (WPI) and its relation to gel properties was investigated. The structural properties of WPI treated with PG were examined by several analytical methods. The analysis of the fluorescence spectrum and the binding capacity of a fluorescent probe demonstrated that deamidation prevented the increase in the fluorescence intensity caused by subsequent heat treatment.

Incorporation of 15N-labeled ammonia into glutamine amide groups by protein-glutaminase and analysis of the reactivity for α-lactalbumin.

Protein-glutaminase (PG) is an enzyme that catalyzes the deamidation of protein-bound glutamine residues. We found that an enzyme labeling technique (ELT), which is a stable isotope labeling method based on transglutaminase (TGase) reaction, is applicable for PG. PG catalyzed incorporation of (15)N-labeled ammonium ions into reactive glutamine amide groups in α-lactalbumin similarly to TGase and deamidated the most reactive glutamine amide group once labeled with (15)N.

Kinetic modeling and sensitivity analysis of xylose metabolism in Lactococcus lactis IO-1.

We proposed a kinetic simulation model of xylose metabolism in Lactococcus lactis IO-1 that describes the dynamic behavior of metabolites using the simulator WinBEST-KIT. This model was developed by comparing the experimental time-course data of metabolites in batch cultures grown in media with initial xylose concentrations of 20.3-57.

New indicators for the evaluation of community policies based on period and cohort effects in cerebrovascular disease mortality rates.

Introduction: Countermeasures against cerebrovascular diseases (CVD) are one of the important health policies in Japan. This study proposes new indicators that are based on period and cohort effects in CVD mortality rates. The main aim of the study is to contribute to community diagnosis with the existing policies.

CtBP1/BARS is an activator of phospholipase D1 necessary for agonist-induced macropinocytosis.

Vesicular trafficking such as macropinocytosis is a dynamic process that requires coordinated interactions between specialized proteins and lipids. A recent report suggests the involvement of CtBP1/BARS in epidermal growth factor (EGF)-induced macropinocytosis. Detailed mechanisms as to how lipid remodelling is regulated during macropinocytosis are still undefined.

[The effects of various factors on cerebrovascular disease mortality rates in the 20th century and future trends in Japan].

Purposes: To analyze the outcomes of measures designed to decrease cerebrovascular diseases (CVDs) in Japan and to project CVD mortality trends into the 21st century based on an analysis of rates observed in the 20th century.

Methods: The numbers of CVD deaths and population sizes from 1920 to 2003 (excluding 1940 to 1946) by sex, year, and 5-year age group (from 20 to 79 years old) were used and effects of various factors on CVD mortality rates were estimated using Nakamura's Bayesian age-period-cohort model. The numbers of CVD deaths up to the year 2050 were projected based on estimates of age, cohort, and future period effects under three scenarios: (i) values remaining constant after year 2003; (ii) linearly extrapolated values; and (iii) quadratically extrapolated values, we obtained using a regression line for period effects from 1995 to 2003.

Involvement of N-terminal-extended form of sphingosine kinase 2 in serum-dependent regulation of cell proliferation and apoptosis.

Sphingosine kinase (SPHK) 1 is implicated in the regulation of cell proliferation and anti-apoptotic processes by catalyzing the formation of an important bioactive messenger, sphingosine 1-phosphate. Unlike the proliferative action of SPHK1, another isozyme, SPHK2, has been shown to possess anti-proliferative or pro-apoptotic action. Molecular mechanisms of SPHK2 action, however, are largely unknown.

Delta-catenin/NPRAP (neural plakophilin-related armadillo repeat protein) interacts with and activates sphingosine kinase 1.

Sphingosine kinase (SPHK) is a key enzyme catalysing the formation of sphingosine 1-phosphate (SPP), a lipid messenger that is implicated in the regulation of a wide variety of important cellular events acting through intracellular, as well as extracellular, mechanisms. However, the molecular mechanism of intracellular actions of SPP remains unclear. Here, we have identified delta-catenin/NPRAP (neural plakophilin-related armadillo repeat protein) as a potential binding partner for SPHK1 by yeast two-hybrid screening.