Simultaneous conversion of free fatty acids and triglycerides to biodiesel by immobilized Aspergillus oryzae expressing Fusarium heterosporum lipase

The presence of high levels of free fatty acids (FFA) in oil is a barrier to one‐step biodiesel production. Undesirable soaps are formed during conventional chemical methods, and enzyme deactivation occurs when enzymatic methods are used. This work investigates an efficient technique to simultaneously convert a mixture of free fatty acids and triglycerides (TAG). A partial soybean hydrolysate containing 73.04% free fatty acids and 24.81% triglycerides was used as a substrate for the enzymatic production of fatty acid methyl ester (FAME). Whole‐cell Candida antarctica lipase B‐expressing Aspergillus oryzae, and Novozym 435 produced only 75.2 and 73.5% FAME, respectively. Fusarium heterosporum lipase‐expressing A. oryzae produced more than 93% FAME in 72 h using three molar equivalents of methanol. FFA and TAG were converted simultaneously in the presence of increasing water content that resulted from esterification. Therefore, F. heterosporum lipase with a noted high level of tolerance of water could be useful in the industrial production of biodiesel from feedstock that has high proportion of free fatty acids.     

Adiponectin protects against myocardial ischemia-reperfusion injury through AMPK- and COX-2-dependent mechanisms

Obesity-related disorders are associated with the development of ischemic heart disease. Adiponectin is a circulating adipose-derived cytokine that is downregulated in obese individuals and after myocardial infarction. Here, we examine the role of adiponectin in myocardial remodeling in response to acute injury. Ischemia-reperfusion in adiponectin-deficient (APN-KO) mice resulted in increased myocardial infarct size, myocardial apoptosis and tumor necrosis factor (TNF)-alpha expression compared with wild-type mice. Administration of adiponectin diminished infarct size, apoptosis and TNF-alpha production in both APN-KO and wild-type mice. In cultured cardiac cells, adiponectin inhibited apoptosis and TNF-alpha production. Dominant negative AMP-activated protein kinase (AMPK) reversed the inhibitory effects of adiponectin on apoptosis but had no effect on the suppressive effect of adiponectin on TNF-alpha production. Adiponectin induced cyclooxygenase (COX)-2-dependent synthesis of prostaglandin E(2) in cardiac cells, and COX-2 inhibition reversed the inhibitory effects of adiponectin on TNF-alpha production and infarct size. These data suggest that adiponectin protects the heart from ischemia-reperfusion injury through both AMPK- and COX-2-dependent mechanisms.     

A seasonal change in the distribution of a stream-dwelling stonefly nymph reflects oxygen supply and water flow

We examined the effects of oxygen availability, which has been viewed as a minor factor in streams, on the seasonal and spatial microhabitat distribution of a stonefly. Surveys were conducted in winter and summer in a mountain stream by collecting stones from the streambed and determining the presence or absence of the insect. At each stone sampling, we also measured physical conditions. The probability of the stonefly presence increased significantly with current velocity in summer, but not in winter. Because current influences oxygen renewal rates, our results suggest that the distribution of the insect could be restricted by oxygen.     

In vivo adenosine receptor preconditioning reduces myocardial infarct size via subcellular ERK signaling

The protective effects of adenosine receptor acute preconditioning (PC) are well known; however, the signaling mechanism mediating this effect has not been determined in in vivo models. The purpose of this study was to determine the role of the extracellular signal-regulated kinase (ERK) pathway in mediating adenosine PC in in vivo rat myocardium. Open-chest rats were submitted to 25 min of coronary artery occlusion and 2 h of reperfusion. ERK activation was assessed by measuring total and dually phosphorylated p44/42 ERK isoforms in nuclear and/or myofilament, mitochondrial, cytosolic, and membrane fractions. Adenosine receptor PC with the A1/A2a agonist 1S-[1a,2b,3b,4a(S*)]-4-[7-[[2-(3-chloro-2-thienyl)-1-methylpropyl]amino]-3H-imidazo[4,5-b]pyridyl-3-yl]cyclopentane carboxamide (AMP-579) reduced infarct size from 49 +/- 3% to 29 +/- 3%, an effect that was blocked by the mitogen-activated protein kinase-ERK inhibitor U-0126. ERK isoforms were present in all fractions, with the greatest expression in the cytosolic fraction and the least in the mitochondrial fraction. AMP-579 treatment increased preischemic p44/42 ERK phosphorylation in all fractions 2.7- to 6.9-fold. Reperfusion increased ERK isoform activation in all fractions, but there were no differences between control and AMP-579 hearts. Preischemic increases in phospo-p44/p42 ERK with AMP-579 were blunted by U-0126, although only in mitochondrial and membrane compartments. The PC effects of AMP-579 on infarct size and ERK were blunted by both the A1 antagonist 8-cyclopentyl-1,3-dipropylxanthine and, surprisingly, the A2a antagonist ZM-241385. These results indicate that the unique adenosine receptor agonist AMP-579 exerts its beneficial effects in vivo via both A1 and A2a receptor modulation of subcellular ERK isoform signaling.     

Rice mutants and genes related to organ development, morphogenesis and physiological traits

Recent advances in genomic studies and the sequenced genome information have made it possible to utilize phenotypic mutants for characterizing relevant genes at the molecular level and reveal their functions. Various mutants and strains expressing phenotypic and physiological variations provide an indispensable source for functional analysis of genes. In this review, we cover almost all of the rice mutants found to date and the variant strains that are important in developmental, physiological and agronomical studies. Mutants and genes showing defects in vegetative organs, i.e. leaf, culm and root, inflorescence reproductive organ and seeds with an embryo and endosperm are described with regards to their phenotypic and molecular characteristics. A variety of alleles detected by quantitative trait locus analysis, such as heading date, disease/insect resistance and stress tolerance, are also shown.     

Involvement of calpain in melanogenesis of mouse B16 melanoma cells

In the current study, the involvement of calpain, a cysteine proteinase in the regulation of melanogenesis was examined using mouse B16 melanoma cells. In response to α-melanocyte-stimulating hormone (α-MSH), B16 melanoma cells underwent differentiation characterized by increased melanin biosynthesis. The total calapain activity was decreased within 2 h following α-MSH-treatment, and restored to the initial level in 6–12 h. To further investigate the involvement of calpain in the regulation of melanogenesis, the effect of calpain inhibitors on α-MSH-induced melanogenesis was examined. Inhibition of calpain by either N-acetyl-Leu-Leu-norleucinal (ALLN) or calpastatin (CS) peptide blocked α-MSH-induced melanogenesis. The magnitude of inhibition of melanin biosynthesis was well correlated with a decrease in the activity of tyrosinase, a key regulatory enzyme in melanogenesis. Treatment of B16 cells with ALLN caused marked decrease in both tyrosinase protein and mRNA levels. These results indicate that calpain would be involved in the melanogenic signaling by modulating the expression of tyrosinase in mouse B16melanoma cells.     

Identification of caffeoylquinic acid derivatives from Brazilian propolis as constituents involved in induction of granulocytic differentiation of HL-60 cells

We have previously reported that Brazilian propolis extracts inhibited growth of HL-60 human myeloid leukemia cells, which is partly attributed to the induction of apoptosis associated with granulocytic differentiation. In this study, we isolated three compounds which induce granulocytic differentiation evaluated by nitroblue tetrazolium (NBT)-reducing assays from the water extract of propolis and identified as 4,5-di-O-caffeoylquinic, 3,5-di-O-caffeoylquinic, and 3,4-di-O-caffeoylquinic acids by NMR analysis. Cell growth inhibitory activity of these caffeoylquinic acids was found in HL-60 cell, which was mainly attributed to the induction of apoptosis. Furthermore, the potency of caffeoylquinic acid derivatives to induce granulocytic differentiation was examined in HL-60 cells. Caffeic, quinic, and chlorogenic acids had no effects on the NBT-reducing activity, while 3,4,5-tri-O-caffeoylquinic acid induced more than 30% of NBT-positive cells. These results suggest that the number of the caffeoyl groups bound to quinic acid plays an important role in the potency of the caffeoylquinic acid derivatives to induce granulocytic differentiation. This is the first report demonstrating that the caffeoylquinic acid derivatives induce granulocytic differentiation of HL-60 cells.     

Epstein-Barr virus lytic replication elicits ATM checkpoint signal transduction while providing an S-phase-like cellular environment

When exposed to genotoxic stress, eukaryotic cells demonstrate a DNA damage response with delay or arrest of cell-cycle progression, providing time for DNA repair. Induction of the Epstein-Barr virus (EBV) lytic program elicited a cellular DNA damage response, with activation of the ataxia telangiectasia-mutated (ATM) signal transduction pathway. Activation of the ATM-Rad3-related (ATR) replication checkpoint pathway, in contrast, was minimal. The DNA damage sensor Mre11-Rad50-Nbs1 (MRN) complex and phosphorylated ATM were recruited and retained in viral replication compartments, recognizing newly synthesized viral DNAs as abnormal DNA structures. Phosphorylated p53 also became concentrated in replication compartments and physically interacted with viral BZLF1 protein. Despite the activation of ATM checkpoint signaling, p53-downstream signaling was blocked, with rather high S-phase CDK activity associated with progression of lytic infection. Therefore, although host cells activate ATM checkpoint signaling with response to the lytic viral DNA synthesis, the virus can skillfully evade this host checkpoint security system and actively promote an S-phase-like environment advantageous for viral lytic replication.     

Identification of proteins phosphorylated directly by the Us3 protein kinase encoded by herpes simplex virus 1

We have developed a system to analyze the specific protein kinase activity of herpes simplex virus 1 Us3 in vitro and shown that Us3 directly phosphorylates viral proteins UL34, ICP22, and Us9 and the cellular protein Bad, previously reported to be putative substrates. Using this system, we determined the phosphorylation sites of UL34 and identified UL31 as a previously unreported, novel substrate of Us3. This system will be useful for further identification of Us3 substrates and their phosphorylation sites, clarification of the role of Us3 in viral replication, and identification of additional Us3 function(s).