Misleading presentations in functional food trials led by contract research organizations were frequently observed in Japan: meta-epidemiological study

OBJECTIVES

The functional food market has experienced significant growth, leading to an uptick in clinical trials conducted by contract research organizations (CROs). Research focusing on CRO-managed trials and the communication of trial outcomes to the consumer market remains underexplored. This metaepidemiological study aims to evaluate the quality of randomized controlled trials (RCTs) facilitated by prominent CROs in Japan and to examine the quality of the representations used to convey their results to consumers.

STUDY DESIGN AND SETTING

This study focused on the food trials that were registered in the University Hospital Medical Information Network Clinical Trial Registry or the International Clinical Trials Registry Platform by the top 5 CROs. Press releases of study results or advertisements of food products based on the study results were identified by conducting a Google search. The risk of bias in the RCT publications was independently assessed by 2 reviewers, who also evaluated the presence of "spin" in the abstracts and full texts. An assessment of "spin" in press releases/advertisements was undertaken.

RESULTS

A total of 76 RCT registrations, 32 RCT publications, and 11 press releases/advertisements were included. Approximately 72% of the RCT publications exhibited a high risk of bias due to selective outcome reporting. "Spin" was present in the results of the abstract (72%), abstract conclusion (81%), full-text results (44%), and full-text conclusion (84%). "Spin" appeared in 73% of press releases/advertisements due to the selective outcome reporting.

CONCLUSION

Functional food presentations in Japan frequently contained "spin." The Japanese government should more rigorously check whether food manufacturers report outcomes selectively.

Comparative efficacy, tolerability and acceptability of intravenous racemic ketamine with intranasal esketamine, aripiprazole and lithium as augmentative treatments for treatment-resistant unipolar depression: A systematic review and network meta-analysis

BACKGROUND

Intravenous racemic ketamine is a promising treatment for treatment-resistant depression. However, its clinical utility compared with intranasal esketamine and the other well-studied conventional pharmacological interventions (i.e., aripiprazole and lithium) as augmentative treatments for treatment-resistant unipolar depression in adults remains unclear. Therefore, we aimed to compare the efficacy, tolerability and acceptability of intravenous racemic ketamine with intranasal esketamine, aripiprazole and lithium under such conditions.

METHODS

The Cochrane Library, PubMed, CINHAL and ClinicalTrials.gov databases were systematically searched from their inception to 10 May 2023. Randomised controlled trials evaluating these drugs were included. A random-effects network meta-analysis was also performed.

RESULTS

In the primary analysis, all four drugs were significantly more effective than placebo. In addition, intravenous racemic ketamine was significantly more effective and acceptable than intranasal esketamine and aripiprazole. Intravenous racemic ketamine was not significantly different from placebo in tolerability, whereas intranasal esketamine and aripiprazole were significantly less tolerable than placebo. Lithium did not differ significantly from intravenous racemic ketamine in efficacy, tolerability and acceptability.

LIMITATIONS

The sample size of patients treated with intravenous racemic ketamine was small.

CONCLUSIONS

Intravenous racemic ketamine may be a better augmentative treatment for treatment-resistant unipolar depression than intranasal esketamine and aripiprazole. Whether intravenous racemic ketamine or lithium is superior is unclear currently. A larger head-to-head trial of intravenous racemic ketamine versus conventional augmentative treatments for treatment-resistant unipolar depression is needed.

Efficacy of telerehabilitation for patients after hip fracture surgery: A systematic review and meta-analysis

INTRODUCTION

This study aimed to determine the efficacy of telerehabilitation for patients after hip fracture surgery through a systematic review and meta-analysis.

METHODS

Eight electronic databases were searched in August 2022. The primary outcomes were mobility outcomes, activities of daily living (ADL) outcomes, and all adverse events, whereas the secondary outcomes were pain, health-related quality of life, and fall efficacy scale score.

RESULTS

Seven randomized controlled trials were eligible for this study. The evidence regarding the effect of telerehabilitation on mobility outcomes (standardized mean difference (SMD): 0.05, 95% confidence interval (CI): -0.39 to 0.48) and all adverse events (risk ratio: 1.14, 95% CI: 0.62 to 2.21) was very uncertain. A clinically irrelevant but significant mean difference (MD) in ADL outcomes was found (MD: 4.82, 95% CI: 2.63 to 7.01). Telerehabilitation may result in a slight increase in fall efficacy scale score (SMD: 0.26, 95% CI: -0.02 to 0.54) and little to no difference in pain (MD: -1.0, 95% CI: -18.31 to 16.31).

CONCLUSIONS

The efficacy of telerehabilitation for patients after hip fracture surgery was uncertain with respect to the mobility outcomes, all adverse events, and pain, with no clinically meaningful differences in ADL outcomes. Telerehabilitation may be necessary to be considered for patients after hip fracture surgery to improve their confidence in their ability to perform daily activities without falling. Therefore, medical staff may consider telerehabilitation for hip fractures.

Changes in neck pain and somatic symptoms before and after the adjustment of the pillow height

[Purpose] The purpose of this study was to determine whether strict adjustment of the pillow height using the Set-up for Spinal Sleep method improves clinical outcomes like neck pain and somatic symptoms. [Participants and Methods] A total of 84 participants with chief complaints of stiff shoulders and neck pain were evaluated using the numerical rating scale and the Somatic Symptom Scale-8. Questionnaires were used to collect data at the baseline, after two weeks, and after three months of adjusting the pillow height. [Results] Forty-two participants (50%) achieved the minimal clinically important difference for neck pain with a decrease of three points or higher in the numerical rating scale. The baseline neck pain scores were significantly higher in the group that achieved the minimal clinically important difference. The three-month change in neck pain and the Somatic Symptom Scale-8 was significantly greater in participants who were satisfied with treatment. There was a significant positive association between improvement in the numerical rating scale score and improvement in the Somatic Symptom Scale-8 at three months. [Conclusion] Strict adjustment of the pillow height using the Set-up for the Spinal Sleep method significantly improved both physical neck pain and somatic symptoms related to psychological and social problems.

Can prior informed consent create virtuous cycle between biodiversity conservation and genetic resources utilization?

This study attempted to predict the effectiveness of prior informed consent (PIC) as a mechanism under the Nagoya Protocol (NP) through the case of Japan, a developed country with a wealth of genetic biodiversity. The NP to the Convention on Biological Diversity (CBD) aims at creating a virtuous cycle between biodiversity conservation and the utilization of genetic resources through fair and equitable benefit sharing. As PIC is a crucial component of the NP for promoting fair and equitable sharing, this study investigated whether introducing PIC creates a virtuous cycle. Considering the limitations of empirical data, this study adopted a policy Delphi comprising experts in an iterative group communication process that used consecutive questionnaires to reveal diverse issues as input for policymaking. We identified six related issues that were evaluated for the case of introduction and three for the case of no introduction of PIC. Their relative importance as a policy concern was measured through best-worst scaling to narrow down policy-relevant issues. This study revealed that contrary to the NP's intent, the overall contribution to the virtuous cycle is limited. In designing PIC mechanisms, policymakers must pay particular attention to bequest and research and development. This study identified three paths through which the negative impacts on research and development further negatively affect bequest, that is, slackening the identification of important genetic resources and ecosystems to conserve, disincentivizing biodiversity conservation for genetic resource use, and dampening ex-situ conservation efforts.

Does the Keele STarT Back Screening Tool Contribute to Effectiveness in Treatment and Cost and Loss of Follow-Up of the Mechanical Diagnosis and Therapy for Patients with Low Back Pain?

Background: Mechanical diagnosis and therapy (MDT) and the stratified approach using the Keele STarT Back Screening Tool (SBST) are examples of stratified low back pain (LBP) management. We investigated whether the medium–high risk in SBST can contribute to the time and sessions until discharge from MDT (Question 1) and to the loss of follow-up before identifying a promising management strategy (Question 2). Methods: A retrospective chart study was conducted. Multiple regression modeling was constructed using 10 independent variables, including whether the SBST was medium–high risk or not for Question 1, and the 9/10 independent variables for Question 2. Results: The data of 89 participants for Question 1 and 166 participants for Question 2 were analyzed. SBST was not a primary contributing factor for Question 1 (R² = 0.17–0.19). The model for Question 2 included SBST as a primary contributing factor and the shortest distance from the patient address to the hospital as a secondary contributing factor (93.4% correct classification). Conclusion: SBST status was not a primary contributing factor for time and sessions until discharge from MDT, but was a critical factor for the loss of MDT follow-up before identifying a promising management strategy.

Long-term evolution of preferences for conservation projects in the Seto Inland Sea, Japan: a comprehensive analytic framework

Background

The long-term evolution of preferences for nature is crucial to conservation projects, given their targeted long-term horizons. Neglecting to account for this evolution could lead to undesirable human–nature relationships. This study compares the willingness to pay (WTP) for three coastal conservation projects in the Seto Inland Sea, Japan, at two distant time points (1998 and 2015), and tests for temporal transferability. It also compares protest responses that are often overlooked in WTP practices, regardless of their utility for conservation projects.

Methods

Given the lack of a unanimous protocol for protest response analyses and their use in estimating WTP, we propose a comprehensive analytic framework that integrates the two.

Results

We show that, while preferences for coastal ecosystem services were overall stable and temporarily transferable, the preferences for certain aspects of conservation projects considerably changed.

Discussion

This suggests the need to reconsider the projects’ scheme, not the ecosystem services themselves, along with the clarification of beneficiaries and those responsible for past destruction. We conclude by suggesting further studies with a focus on regions experiencing significant social-ecological changes, such as developing countries, by exploiting the rich asset of existing valuations. This could contribute to the database for more temporal-sensitive ecosystem service valuations utilized for benefit transfers.

Best-worst scaling survey of preferences regarding the adverse effects of tobacco use in China

We use best–worst scaling to assess two types of concern levels of the adverse consequences of smoking in China. While the smoking cessation policy has worked well in Taiwan, more than 1 million people in mainland China are estimated to die every year from tobacco use. This study compares the preferences of Chinese individuals in the two jurisdictions (mainland versus Taiwan) and explores the possibility of information-based interventions. The relative importance of 13 adverse effects was assessed by conducting a web-based survey on a sample of 480 Chinese participants. The 13 items consist of various adverse effects of tobacco use: from long-term health risk, such as lung cancer and cardiovascular diseases, to reduction of physical capacity and sexual dysfunction, and disturbance to non-smokers. The resulting data suggest possible strategies to curb smoking. Subgroup analysis, focusing on gender, smoking status, and nicotine dependence, was also conducted. Lung cancer, cardiovascular diseases, and chronic obstructive pulmonary disease, in this order, rank highest for both types of respondents. On the other hand, high expenditures (13th) and weight gain after cessation (12th) are the lowest ranked for both. Measuring individual best–worst scores reveals substantial heterogeneity among respondents and that information-based intervention can help curb smoking.

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Best-worst scaling (BWS) is used to assess concerns on tobacco adverse effects.

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Adverse effects of tobacco are assessed for mainland and Taiwan residents.

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Lung cancer, cardiovascular diseases, and COPD rank highest for both.

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Information-based interventions are explored for Chinese smokers.

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Comparative results provide insights for a future anti-smoking policy.

A robust route to enzymatically functional, hierarchically self-assembled peptide frameworks

The addition of enzyme biofunctionality to self-assembling peptide nanofibers is challenging since such additions can inhibit functionality or self-assembly. We introduce a method for peptide nanofiber enzyme functionalization, demonstrated by the attachment of a polymerization synthase to peptide nanofibers. The enzyme generates a biocompatible, biodegradable biopolyester coat on the fibers with applicablity in medical engineering. This approach provides a template for generation of functional bionanomaterials.

Expression of Aeromonas caviae polyhydroxyalkanoate synthase gene in Burkholderia sp. USM (JCM15050) enables the biosynthesis of SCL-MCL PHA from palm oil products

AIMS

Burkholderia sp. USM (JCM15050) isolated from oil-polluted wastewater is capable of utilizing palm oil products and glycerol to synthesize poly(3-hydroxybutyrate) [P(3HB)]. To confer the ability to produce polymer containing 3-hydroxyhexanoate (3HHx), plasmid (pBBREE32d13) harbouring the polyhydroxyalkanoate (PHA) synthase gene of Aeromonas caviae (phaC(Ac)) was transformed into this strain.

METHODS AND RESULTS

  The resulting transformant incorporated approximately 1 ± 0·3 mol% of 3HHx in the polymer when crude palm kernel oil (CPKO) or palm kernel acid oil was used as the sole carbon source. In addition, when the transformed strain was cultivated in the mixtures of CPKO and sodium valerate, PHA containing 69 mol% 3HB, 30 mol% 3-hydroxyvalerate and 1 mol% 3HHx monomers was produced. Batch feeding of carbon sources with 0·5% (v/v) CPKO at 0 h and 0·25% (w/v) sodium valerate at 36 h yielded 6 mol% of 3HHx monomer by controlled-feeding strategies.

CONCLUSIONS

Burkholderia sp. USM (JCM15050) has the metabolic pathways to supply both the short-chain length (SCL) and medium-chain length (MCL) PHA monomers. By transforming the strain with the Aer. caviae PHA synthase with broader substrate specificity, SCL-MCL PHA was produced.

SIGNIFICANCE AND IMPACT OF THE STUDY

  This is the first study demonstrating the ability of transformant Burkholderia to produce P(3HB-co-3HHx) from a single carbon source.

Nuclear Ribosomal DNA as a Probe for Genetic Variability in the Japanese Pear Pathotype of Alternaria alternata

A restriction fragment length polymorphism analysis of nuclear ribosomal RNA genes (rDNA) was used to measure the amount and distribution of genetic variability in populations of the Japanese pear pathotype of Alternaria alternata on both micro- and macrogeographical scales. A total of 322 isolates were obtained from 13 areas in Aichi, Gifu, and Tottori Prefectures in central and western Japan. The restriction fragment length polymorphism analysis revealed that the pathogen populations contained at least eight rDNA variants. The eight variant types differed in the lengths and in the presence of the restriction sites in spacer DNA outside the coding regions for rRNAs. A total of 271 isolates were classified into the eight types. The remaining 51 isolates were determined to have mixed rDNA types. Single pear fields typically contained two to five types of rDNA variants. The frequencies of rDNA variants in 11 populations in Tottori Prefecture were compared; in this prefecture orchards containing the susceptible pear are common. Except for one collection site, there were no significant differences in the composition of the rDNA variants among the populations. This suggests that dispersal of inocula has occurred frequently in Tottori Prefecture. In contrast, significantly different distributions were observed in the three prefectures, indicating that gene flow between prefectures might be limited by geographical isolation. DNA fingerprints resulting from hybridization with a moderately repetitive DNA sequence of the fungus revealed greater genetic variability and geographical differences in genetic population structure even within the same rDNA type.

ACTTS3 encoding a polyketide synthase is essential for the biosynthesis of ACT-toxin and pathogenicity in the tangerine pathotype of Alternaria alternata

The tangerine pathotype of Alternaria alternata produces host-selective ACT-toxin and causes Alternaria brown spot disease of tangerine and tangerine hybrids. Sequence analysis of a genomic BAC clone identified part of the ACT-toxin TOX (ACTT) gene cluster, and knockout experiments have implicated several open reading frames (ORF) contained within the cluster in the biosynthesis of ACT-toxin. One of the ORF, designated ACTTS3, encoding a putative polyketide synthase, was isolated by rapid amplification of cDNA ends and genomic/reverse transcription-polymerase chain reactions using the specific primers designed from the BAC sequences. The 7,374-bp ORF encodes a polyketide synthase with putative beta-ketoacyl synthase, acyltransferase, methyltransferase, beta-ketoacyl reductase, and phosphopantetheine attachment site domains. Genomic Southern blots demonstrated that ACTTS3 is present on the smallest chromosome in the tangerine pathotype of A. alternata, and the presence of ACTTS3 is highly correlated with ACT-toxin production and pathogenicity. Targeted gene disruption of two copies of ACTTS3 led to a complete loss of ACT-toxin production and pathogenicity. These results indicate that ACTTS3 is an essential gene for ACT-toxin biosynthesis in the tangerine pathotype of A. alternata and is required for pathogenicity of this fungus.

Function of genes encoding acyl-CoA synthetase and enoyl-CoA hydratase for host-selective act-toxin biosynthesis in the tangerine pathotype of Alternaria alternata

The tangerine pathotype of Alternaria alternata produces host-selective ACT-toxin and causes Alternaria brown spot disease. Sequence analysis of a genomic cosmid clone identified a part of the ACTT gene cluster and implicated two genes, ACTT5 encoding an acyl-CoA synthetase and ACTT6 encoding an enoyl-CoA hydratase, in the biosynthesis of ACT-toxin. Genomic Southern blots demonstrated that both genes were present in tangerine pathotype isolates producing ACT-toxin and also in Japanese pear pathotype isolates producing AK-toxin and strawberry pathotype isolates producing AF-toxin. ACT-, AK-, and AF-toxins from these three pathotypes share a common 9,10-epoxy-8-hydroxy-9-methyl-decatrienoic acid moiety. Targeted gene disruption of two copies of ACTT5 significantly reduced ACT-toxin production and virulence. Targeted gene disruption of two copies of ACTT6 led to complete loss of ACT-toxin production and pathogenicity and a putative decatrienoic acid intermediate in ACT-toxin biosynthesis accumulated in mycelial mats. These results indicate that ACTT5 and ACTT6 are essential genes in ACT-toxin biosynthesis in the tangerine pathotype of A. alternata and both are required for full virulence of this fungus.

Functional analysis of a multicopy host-selective ACT-toxin biosynthesis gene in the tangerine pathotype of Alternaria alternata using RNA silencing

Alternaria brown spot, caused by the tangerine pathotype of Alternaria alternata, is a serious disease of commercially important tangerines and their hybrids. The pathogen produces host-selective ACT toxin, and several genes (named ACTT) responsible for ACT-toxin biosynthesis have been identified. These genes have many paralogs, which are clustered on a small, conditionally dispensable chromosome, making it difficult to disrupt entire functional copies of ACTT genes using homologous recombination-mediated gene disruption. To overcome this problem, we attempted to use RNA silencing, which has never been employed in Alternaria spp., to knock down the functional copies of one ACTT gene with a single silencing event. ACTT2, which encodes a putative hydrolase and is present in multiple copies in the genome, was silenced by transforming the fungus with a plasmid construct expressing hairpin ACTT2 RNAs. The ACTT2 RNA-silenced transformant (S-7-24-2) completely lost ACTT2 transcripts and ACT-toxin production as well as pathogenicity. These results indicated that RNA silencing may be a useful technique for studying the role of ACTT genes responsible for host-selective toxin biosynthesis in A. alternata. Further, this technique may be broadly applicable to the analysis of many genes present in multiple copies in fungal genomes that are difficult to analyze using recombination-mediated knockdowns.

Nitrite reductase gene upregulated during conidiation is involved in macroconidium formation in Fusarium oxysporum

Fusarium oxysporum produces three kinds of asexual spores, microconidia, macroconidia, and chlamydospores. We previously found that the transcript level of the nitrite reductase gene of F. oxysporum, named FoNIIA, was markedly upregulated during conidiation compared with during vegetative growth. FoNIIA was also found to be positively regulated by Ren1 that is a transcription regulator controlling development of microconidia and macroconidia. In this study, we analyzed the function of FoNIIA in conidiation of F. oxysporum. Conidiation cultures showed markedly higher level of accumulation of FoNiiA protein as well as FoNIIA mRNA than vegetative growth cultures. FoNIIA protein was significantly decreased in cultures of the REN1 disruption mutant compared with that of the wild type. These results confirmed that FoNIIA expression is upregulated during conidiation and is positively regulated by REN1. The FoNIIA disruption mutants produced microconidia, macroconidia, and chlamydospores, which were morphologically indistinguishable from those of the wild type. The mutants, however, produced significantly fewer macroconidia than the wild type, although the wild type and mutant strains produced similar numbers of microconidia and chlamydospores. These results demonstrate that nitrite reductase is involved in quantitative control of macroconidium formation as well as nitrate utilization in F. oxysporum.

Development of a novel method for feeding a mixture of L-lactic acid and acetic acid in fed-batch culture of Ralstonia eutropha for poly-D-3-hydroxybutyrate production

Fermentative production of poly-D-3-hydroxybutyrate [P(3HB)] from a mixture of L-lactic acid and acetic acid by Ralstonia eutropha was investigated. For fed-batch culture with cell density, it is necessary to control the concentration of these organic acids in the culture medium below the inhibitory level for cell growth. Therefore, a novel feeding method, termed the computer-controlled pH-stat substrate feeding method, was developed using the rate of increase of the pH (pH-increasing rate) of the culture medium as an indicator for feed control. The pH-increasing rate, which was calculated every minute by a pH meter-linked computer, represented secondary information regarding substrate consumption by cells. When the pH-increasing rate decreased to 5% of the maximum increasing rate, acidic substrate solution was fed into the fermentor until the pH was reduced to 7.00. Using this feeding strategy, the cell concentration and PHA content obtained in 42 h were 75.0 g/l and 73.1% (w/w), respectively, resulting in a high P(3HB) productivity of 1.30 g/l.h.

An Isolate of Alternaria alternata That Is Pathogenic to Both Tangerines and Rough Lemon and Produces Two Host-Selective Toxins, ACT- and ACR-Toxins

ABSTRACT Two different pathotypes of Alternaria alternata cause Alternaria brown spot of tangerines and Alternaria leaf spot of rough lemon. The former produces the host-selective ACT-toxin and the latter produces ACR-toxin. Both pathogens induce similar symptoms on leaves or young fruits of their respective hosts, but the host ranges of these pathogens are distinct and one pathogen can be easily distinguished from another by comparing host ranges. We isolated strain BC3-5-1-OS2A from a leaf spot on rough lemon in Florida, and this isolate is pathogenic on both cv. Iyokan tangor and rough lemon and also produces both ACT-toxin and ACR-toxin. Isolate BC3-5-1-OS2A carries both genomic regions, one of which was known only to be present in ACT-toxin producers and the other was known to exist only in ACR-toxin producers. Each of the genomic regions is present on distinct small chromosomes, one of 1.05 Mb and the other of 2.0 Mb. Alternaria species have no known sexual or parasexual cycle in nature and populations of A. alternata on citrus are clonal. Therefore, the ability to produce both toxins was not likely acquired through meiotic or mitotic recombination. We hypothesize that a dispensable chromosome carrying the gene cluster controlling biosynthesis of one of the host-selective toxins was transferred horizontally and rearranged by duplication or translocation in another isolate of the fungus carrying genes for biosynthesis of the other host-selective toxin.

Monocyte chemoattractant protein (MCP)-1 production via functionally reconstituted Fcalpha receptor (CD89) on glomerular mesangial cells

BACKGROUND

Fc alpha receptor (FcalphaR; CD89) is the receptor for Fc portion of IgA in various cells, and displays various immunological responses on binding. It is important to analyze the mesangial functions via FcalphaR in the pathogenesis of IgA nephropathy. However, it is still controversial whether FcalphaR is expressed on mesangial cells. To assess biological functions of FcalphaR on the mesangial cells, we established mesangial transfectants that expressed FcalphaR with or without FcRgamma chain that is a common signaling molecule of FcRs. The production of monocyte chemoattractant protein-1 (MCP-1) by mesangial cells is known to contribute to cellular infiltration into glomeruli and subsequent glomerular injuries.

METHODS

Murine mesangial cell lines (SV40 MES 13) were transfected with cDNA of the human FcalphaR. Furthermore, we co-transfected some of the FcalphaR transfectants with cDNA of human FcRgamma chain. The tyrosine phosphorylation of the intra-mesangial proteins after FcalphaR cross-linking was examined by immunoprecipitation. MCP-1 production from each transfectant stimulated with heat aggregated IgA was determined by sandwich ELISA.

RESULTS

Two kinds of mesangial transfectants stably expressed human FcalphaR with or without FcRgamma chain (FcalphaR(+), FcalphaR(+)/gamma(+)). Phosphorylation of FcRgamma chain and syk kinase was detected in FcalphaR(+) and FcalphaR(+)/gamma(+) cells, but not in untransfected cells. Aggregated IgA induced significantly higher MCP-1 production in FcalphaR(+)/gamma(+) than those in FcalphaR(+) or untransfected control.

CONCLUSIONS

Present study demonstrated that FcalphaR and FcRgamma chain could be reconstituted in mesangial cells and mediated MCP-1 production by aggregated IgA in a dose-dependent manner. Current data would argue that FcalphaR can be activated in mesangial cells through their own machinery, although underlying mechanisms for FcalphaR induction in mesangial cells remain unclear.

Economic valuation of the Seto Inland Sea by using an Internet CV survey

We estimate the economic value of the natural environment damaged in the Seto Inland Sea after the introduction of the Law on Temporary Measures for the Environmental Conservation of the Seto Inland Sea (Setouchi Law) and the value of the natural environment that survived, using a Contingent Valuation (CV) survey on an Internet web site. The CV survey contains three plans. Plan 1 is to restore 4 ha of reclaimed land. By estimating the Willingness To Pay (WTP) for plan 1, we can appraise the value of the natural environment that was damaged as a result of the original reclamation. Plan 2 is to transplant Zostera (eel-grass) into an area of 10 ha offshore. Plan 3 is to preserve the shore area, a natural habitat for rare animal species, under the National Trust Program. From the WTP for plans 2 and 3, we can estimate the value of the shore area and the areas a little farther offshore. The value of the natural environment damaged in the Seto Inland Sea as a result of reclaiming projects after the introduction of the Setouchi Law and the value of the existing natural environment of the Seto Inland Sea from the WTP for the plans were estimated to about 172 trillion yen (1.46 trillion dollars) and about 424 trillion yen (3.60 trillion dollars), respectively. The results indicate that in the 25 years since the introduction of the Setouchi Law, we have degraded every year about 6.88 trillion yen (58.5 billion dollars) worth of the natural environment by reclaiming. Some seaweed farms and natural shore areas, natural habitats to rare marine life-forms like the horseshoe crab and the fiddler crab have survived, but their value amounts to about 80% of Japan's GDP.

Surgical decision-making on cerebral cavernous malformations

This study is an attempt to clarify surgical decision-making on cerebral cavernous malformations based on the data available in the literature. Using a mathematical model, we calculated the morbidity-free survival curves of the patients harboring cerebral cavernous malformations. Using these survival curves, we calculated the morbidity-free life expectancies of the patients at certain age undergoing either natural course or surgery. For superficially located lesions, permissible surgical risks were very small ranging from 0.4 to 2.8 percent of combined morbidity and mortality. The surgical gain of morbidity free life expectancy was also very small (0.0-1.1 years) irrespective of patient's age or eloquence of the location. For deep lesions, the permissible risk of surgery was very large, ranging from 64.1% for a 20-year-old and 31.4% for a 60-year-old patient. The gain of morbidity-free life expectancy was also large for younger patients (17-25 years for 20-year-old patients), but this gain rapidly decreased as the patient's age grew older, becoming 1.1 to 3.1 years for 60-year-old patients. Surgery seems to be justified for younger patients with deep lesions. There seems to be little indication for surgery of superficial lesions as far as the risk of bleeding is concerned.

Phytochrome-mediated control of COP1 gene expression in rice plants

We isolated a COP1 cDNA from rice and found that it could complement the Arabidopsis cop1-4 mutant. The putative rice COP1 protein has the Ring-finger, coiled-coil. and WD-40 repeat domains, which are also conserved in pea, tomato, and mammalian COP1 proteins. The degree of overall identity between rice COP1 and Arabidopsis COP1 is 73%, and the similarity value is 83%. Expression of rice COP1 was detected in almost all plant tissues, with the level being relatively higher in calli and very low in etiolated leaves. The expression level was positively controlled by light in etiolated and green leaves. At the end of the light period, expression of the gene in green leaves could be down-regulated by far-red light. This far-red light effect could be prevented by subsequent irradiation with red light. These results indicate that phytochrome regulates rice COP1 expression.

Promotion of NEDD-CUL1 conjugate cleavage by COP9 signalosome

SCF ubiquitin ligases control various processes by marking regulatory proteins for ubiquitin-dependent proteolysis. To illuminate how SCF complexes are regulated, we sought proteins that interact with the human SCF component CUL1. The COP9 signalosome (CSN), a suppressor of plant photomorphogenesis, associated with multiple cullins and promoted cleavage of the ubiquitin-like protein NEDD8 from Schizosaccharomyces pombe CUL1 in vivo and in vitro. Multiple NEDD8-modified proteins uniquely accumulated in CSN-deficient S. pombe cells. We propose that the broad spectrum of activities previously attributed to CSN subunits--including repression of photomorphogenesis, activation of JUN, and activation of p27 nuclear export--underscores the importance of dynamic cycles of NEDD8 attachment and removal in biological regulation.

Mutation of an arginine biosynthesis gene causes reduced pathogenicity in Fusarium oxysporum f. sp. melonis

Restriction enzyme-mediated integration (REMI) mutagenesis was used to tag genes required for pathogenicity of Fusarium oxysporum f. sp. melonis. Of the 1,129 REMI transformants tested, 13 showed reduced pathogenicity on susceptible melon cultivars. One of the mutants, FMMP95-1, was an arginine auxotroph. Structural analysis of the tagged site in FMMP95-1 identified a gene, designated ARG1, which possibly encodes argininosuccinate lyase, catalyzing the last step for arginine biosynthesis. Complementation of FMMP95-1 with the ARG1 gene caused a recovery in pathogenicity, indicating that arginine auxotrophic mutation causes reduced pathogenicity in this pathogen.

Polymorphism in promoter region of Fcalpha receptor gene in patients with IgA nephropathy

We have recently identified two novel polymorphisms (-114T/C and +56T/C relative to the major transcription start site) in the functional promoter region of the Fcalpha receptor (FcalphaR) gene. Since altered FcalphaR expression may be associated with IgA nephropathy, we examined these promoter polymorphisms in this disease. Patients with IgA nephropathy (n = 90), patients with other primary glomerulonephritis (n = 50), and healthy adults (n = 83) were studied. Genotyping was performed by the polymerase chain reaction (PCR) followed by direct sequence analysis and was subsequently confirmed by PCR with mismatched primers followed by restriction fragment length polymorphism analysis. The study demonstrated that the frequency of the +56C allele in patients with IgA nephropathy (0.511) was significantly (P < 0.01) higher than that in patients with other primary glomerulonephritis (0.350) and healthy adults (0.337). In addition, a significant increase in the frequency of the +56CC genotype was observed in patients with IgA nephropathy (27.8% vs 10.0% in other GN and vs 9.6% in healthy adults). In contrast, no significant difference in the frequencies of the +56CC genotype and +56C allele was observed between other primary glomerulonephritis patients and healthy adults. The frequency of the -114CC genotype in patients with IgA nephropathy was significantly increased compared with those in both control groups (15.6% vs 4.0% in other GN and vs 2.4% in healthy adults). Polymorphisms of the FcalphaR promoter region therefore appear to be associated with susceptibility to IgA nephropathy, suggesting the importance of the FcalphaR gene and its expression in this disease.

The subunit 1 of the COP9 signalosome suppresses gene expression through its N-terminal domain and incorporates into the complex through the PCI domain

The COP9 signalosome is a conserved protein complex composed of eight subunits. Individual subunits of the complex have been linked to various signal transduction pathways leading to gene expression and cell cycle control. However, it is not understood how each subunit executes these activities as part of a large protein complex. In this study, we dissected structure and function of the subunit 1 (CSN1 or GPS1) of the COP9 signalosome relative to the complex. We demonstrated that the C-terminal half of CSN1 encompassing the PCI domain is responsible for interaction with CSN2, CSN3, and CSN4 subunits and is required for incorporation of the subunit into the complex. The N-terminal fragment of CSN1 cannot stably associate with the complex but can translocate to the nucleus on its own. We further show that CSN1 or the N-terminal fragment of CSN1 (CSN1-N) can inhibit c-fos expression from either a transfected template or a chromosomal transgene ( fos-lacZ). Moreover, CSN1 as well as CSN1-N can potently suppress signal activation of a AP-1 promoter and moderately suppress serum activation of a SRE promoter, but is unable to inhibit PKA-induced CRE promoter activity. We conclude that the N-terminal half of CSN1 harbors the activity domain that confers most of the repression functions of CSN1 while the C-terminal half allows integration of the protein into the COP9 signalosome.

Identification and characterization of the promoter for the gene encoding the human myeloid IgA Fc receptor (FcalphaR, CD89)

The Fc receptor for IgA (FcalphaR, CD89), a transmembrane glycoprotein, is expressed exclusively on human phagocytic cells including monocytes, macrophages, eosinophils, and neutrophils, and is capable of triggering various effector functions. In the present study, we identified and characterized, for the first time, the FcalphaR promoter. A 929-bp fragment of FcalphaR 5'-flanking sequence directed expression of a reporter gene specifically in monocytic cell line U937. Deletion analyses localized element(s) directing tissue-specific reporter gene expression to the 259 bp proximal to the translation initiation site. Within the region, the sequence between 59 and 197 bp downstream of the major transcription start site was shown to be essential for promoter activity. This sequence contains multiple potential binding sites for transcription factors which have been reported to function in myeloid-specific gene expression, including three CCAAT enhancer-binding protein (C/EBP)-binding sites, an NF-kappaB-binding site, an Spl site, an Ets family protein consensus-binding site, and a Myb-binding site. In addition, we identified two polymorphisms (C-->T transition) at the positions 114 bp upstream and 56 bp downstream of the major transcription start site, and demonstrated that the FcalphaR promoter region carrying both the -114T and +56T alleles had significantly lower promoter activity than that harboring the C alleles at both sites. Characterization of this promoter will facilitate further analyses of activation stimuli and transcription factors involved in FcalphaR-mediated immune system, and provide new insights into the mechanism(s) underlying altered FcalphaR expression associated with diseases such as allergic diseaes and IgA nephropathy.

Structural and functional complexity of the genomic region controlling AK-toxin biosynthesis and pathogenicity in the Japanese pear pathotype of Alternaria alternata

The Japanese pear pathotype of Alternaria alternata produces host-specific AK-toxin and causes black spot of Japanese pear. Previously, a cosmid clone, pcAKT-1, was isolated that contains two genes, AKT1 and AKT2, within a 5.0-kb region required for AK-toxin biosynthesis. The wild-type strain has multiple, nonfunctional copies of these genes. In the present study, two additional genes, AKTR-1 and AKT3-1, downstream of AKT2 were identified. Transformation of the wild type with AKTR-1- and AKT3-1-targeting vectors produced toxin-deficient (Tox-), nonpathogenic mutants. DNA gel blot analysis, however, demonstrated that the fragments targeted in Tox- mutants were different from those containing AKTR-1 and AKT3-1 on the transforming vectors. A cosmid clone, pcAKT-2, containing the targeted DNA was isolated and shown to carry two genes, AKTR-2 and AKT3-2, with high similarity to AKTR-1 and AKT3-1, respectively. Transcripts from not only AKTR-2 and AKT3-2 but also AKTR-1 and AKT3-1 were found in the wild type. DNA gel blot analysis with pulsed-field gel electrophoresis showed that AKT1, AKT2, AKT3, and AKTR and their homologues are on a single chromosome. These results indicate the structural and functional complexity of the genomic region controlling AK-toxin biosynthesis.

Distribution and Characterization of AKT Homologs in the Tangerine Pathotype of Alternaria alternata

ABSTRACT The tangerine pathotype of Alternaria alternata produces a host-selective toxin (HST), known as ACT-toxin, and causes Alternaria brown spot disease of citrus. The structure of ACT-toxin is closely related to AK- and AF-toxins, which are HSTs produced by the Japanese pear and strawberry pathotypes of A. alternata, respectively. AC-, AK-, and AF-toxins are chemically similar and share a 9,10-epoxy-8-hydroxy-9-methyl-decatrienoic acid moiety. Two genes controlling AK-toxin biosynthesis (AKT1 and AKT2) were recently cloned from the Japanese pear pathotype of A. alternata. Portions of these genes were used as heterologous probes in Southern blots, that detected homologs in 13 isolates of A. alternata tangerine pathotype from Minneola tangelo in Florida. Partial sequencing of the homologs in one of these isolates demonstrated high sequence similarity to AKT1 (89.8%) and to AKT2 (90.7%). AKT homologs were not detected in nine isolates of A. alternata from rough lemon, six isolates of nonpathogenic A. alternata, and one isolate of A. citri that causes citrus black rot. The presence of homologs in the Minneola isolates and not in the rough lemon isolates, nonpathogens or black rot isolates, correlates perfectly to pathogenicity on Iyo tangerine and ACT-toxin production. Functionality of the homologs was demonstrated by detection of transcripts using reverse transcription-polymerase chain reaction (RT-PCR) in total RNA of the tangerine pathotype of A. alternata. The high sequence similarity of AKT and AKT homologs in the tangerine patho-type, combined with the structural similarity of AK-toxin and ACT-toxin, may indicate that these homologs are involved in the biosynthesis of the decatrienoic acid moiety of ACT-toxin.

REAL, an LTR retrotransposon from the plant pathogenic fungus Alternaria alternata

A retrotransposon was isolated and characterized from strain 15A of the Japanese pear pathotype of Alternaria alternata, which causes black spot disease in certain cultivars of Japanese pear by producing a host-specific toxin known as AK-toxin. The element, which we have named REAL (Retrotransposon of Alternaria alternata), is 6046 bp in size and contains direct long terminal repeats (LTRs) of 218 bp. Target-site duplication of 5 bp was found. REAL contains two long overlapping ORFs. The first ORF shows homology to retroviral gag genes. The second ORF has homology to protease, reverse transcriptase, RNase H and integrase domains of the retroelement pol genes, in that order. Phylogenetic comparison of reverse transcriptase domains from retrotransposons placed REAL in the Ty3/gypsy group of LTR retrotransposons, most closely related to grasshopper from Magnaporthe grisea. Northern analysis detected REAL transcripts of about 2.0 and 6.0 kb. The 6.0-kb species corresponds to a full-length transcript of the element. The element was found by Southern analysis in 12 out of 13 strains of the Japanese pear pathotype, and the banding patterns, copy numbers and signal intensities in these strains were variable. REAL-related elements were also found in some, but not all, of the other strains tested, including nonpathogenic A. alternata and other pathotypes, which cause diseases on different plant species by producing distinct hostspecific toxins. These results suggest that the distribution of REAL in A. alternata is not pathotype specific.

Effect of mizoribine on glomerulonephritis of early-stage IgA nephropathy in ddY mice

Immunopathological studies were performed to determine whether the glomerular injuries in ddY mice, a model for IgA nephropathy (Berger's disease), are influenced by treatment with mizoribine, a new immunosuppressive agent. The ddY mice were treated with a low (0.05 mg/ml) or a high (0.1 mg/ml) dose of mizoribine for 35 weeks. Flow cytometry analysis showed that there was a marked decrease in the number of B cells and IgA-bearing B cells. In immunofluorescence, the deposition of IgA in the glomerular mesangial areas and capillary walls of the high-dose mizoribine-treated ddY mice was markedly decreased as compared with that of control ddY mice receiving drinking water. The glomerular mesangial expansion in the high-dose mizoribine-treated ddY mice was milder than that found in the control ddY mice. In 45-week-old ddY mice, the average number of intraglomerular cells in the high-dose and low-dose mizoribine-treated ddY mice was slightly lower than that in drinking water treated ddY mice. The levels of urinary protein excretion in the high-dose mizoribine-treated ddY mice were also lower than those in the low-dose mizoribine-treated or drinking water treated ddY mice. It appears that treatment of mizoribine might influence the proliferation of B cells, especially IgA-bearing B cells, and improve the glomerular IgA deposition and glomerular expansion in early-stage IgA nephropathy of ddY mice.

Molecular cloning of two (R)-specific enoyl-CoA hydratase genes from Pseudomonas aeruginosa and their use for polyhydroxyalkanoate synthesis

Two Pseudomonas aeruginosa genes, termed phaJ1(Pa) and phaJ2(Pa), homologous to the Aeromonas caviae (R)-specific enoyl-CoA hydratase gene (phaJ(Ac)) were cloned using a PCR technique to investigate the monomer-supplying ability for polyhydroxyalkanoate (PHA) synthesis from beta-oxidation cycle. Two expression plasmids for phaJ1(Pa) and phaJ2(Pa) were constructed and introduced into Escherichia coli DH5alpha strain. The recombinants harboring phaJ1(Pa) or phaJ2(Pa) showed high (R)-specific enoyl-CoA hydratase activity with different substrate specificities, that is, specific for short chain-length enoyl-CoA or medium chain-length enoyl-CoA, respectively. In addition, co-expression of these two hydratase genes with PHA synthase gene in E. coli LS5218 resulted in the accumulation of PHA up to 14-29 wt% of cell dry weight from dodecanoate as a sole carbon source. It has been suggested that phaJ1(Pa) and phaJ2(Pa) products have the monomer-supplying ability for PHA synthesis from beta-oxidation cycle.

Infiltrating dendritic/Langerhans cells in primary breast cancer

It is fully anticipated that dendritic cells (DCs) will become a mainstay for inclusion in biological therapies for patients with cancer including breast cancer. To elucidate the cellular composition of DCs infiltrating human breast cancers, we investigated the correlations between the density of infiltrating DCs and some clinicopathological factors of breast cancer patients, examined cytokine expression on cancer cells and finally, assessed the numbers of CD45RO+ tumor infiltrating lymphocytes (TIL). Tissues adjacent to cancer nests contained significantly more S-100 protein+ and S-100 protein+ CD1a- DCs, but less CD1a+ DCs, than the nests. In invasive ductal carcinomas infiltration by S-100 protein+ DCs within and adjacent to nests, CD1a+ DCs within nests and S-100 protein+ CD1a- DCs adjacent to nests was denser than that in non-invasive carcinomas. With respect to the histological subtypes, there were fewer DCs in scirrhous carcinomas. Patients with stage IV disease had significantly fewer DCs of primary lesions than at other clinical stages. There were good correlations between infiltration by S-100 protein+ DCs and expression of the cytokines GM-CSF, IL-1alpha and TNF-alpha on cancer cells and between GM-CSF expression and S-100 protein+ CD1a- DCs. There was a close correlation between CD45RO+ TIL and S-100 protein+ DC densities both within and adjacent to the cancer nests and the S-100 protein+ CD1a- DC density adjacent to the cancer nests. Despite extensive immunoelectron microscopic observation, CD1a+ DCs within cancer nests contained only few Birbeck's granule-like structure. These data indicate that cancer nests are infiltrated predominantly by CD1a+ DCs, whereas S-100 protein+ CD1a- DCs predominate in surrounding tissues, and a infiltration by DCs may require cytokine expression on cancer cells and simultaneous lymphocyte infiltration. The findings of this clinicopathological study indicate the importance of evaluating simultaneously the types and localizations of infiltrating DCs in cancer tissues.

Arabidopsis cop8 and fus4 mutations define the same gene that encodes subunit 4 of the COP9 signalosome

The pleiotropic constitutive photomorphogenic/deetiolated/fusca (cop/det/fus) mutants of Arabidopsis exhibit features of light-grown seedlings when grown in the dark. Cloning and biochemical analysis of COP9 have revealed that it is a component of a multiprotein complex, the COP9 signalosome (previously known as the COP9 complex). Here, we compare the immunoaffinity and the biochemical purification of the COP9 signalosome from cauliflower and confirm its eight-subunit composition. Molecular cloning of subunit 4 of the complex revealed that it is a proteasome-COP9 complex-eIF3 domain protein encoded by a gene that maps to chromosome 5, near the chromosomal location of the cop8 and fus4 mutations. Genetic complementation tests showed that the cop8 and fus4 mutations define the same locus, now designated as COP8. Molecular analysis of the subunit 4-encoding gene in both cop8 and fus4 mutants identified specific molecular lesions, and overexpression of the subunit 4 cDNA in a cop8 mutant background resulted in complete rescue of the mutant phenotype. Thus, we conclude that COP8 encodes subunit 4 of the COP9 signalosome. Examination of possible molecular interactions by using the yeast two-hybrid assay indicated that COP8 is capable of strong self-association as well as interaction with COP9, FUS6/COP11, FUS5, and Arabidopsis JAB1 homolog 1, the latter four proteins being previously defined subunits of the Arabidopsis COP9 signalosome. A comparative sequence analysis indicated that COP8 is highly conserved among multicellular eukaryotes and is also similar to a subunit of the 19S regulatory particle of the 26S proteasome.

Insertional mutagenesis and cloning of the genes required for biosynthesis of the host-specific AK-toxin in the Japanese pear pathotype of Alternaria alternata

The Japanese pear pathotype of Alternaria alternata causes black spot of Japanese pear by producing a host-specific toxin known as AK-toxin. Restriction enzyme-mediated integration (REMI) mutagenesis was used to tag genes required for toxin biosynthesis. Protoplasts of a wild-type strain were treated with a linearized plasmid along with the restriction enzyme used to linearize the plasmid. Of 984 REMI transformants recovered, three produced no detectable AK-toxin and lost pathogenicity on pear leaves. Genomic DNA flanking the integrated plasmid was recovered from one of the mutants. With the recovered DNA used as a probe, a cosmid clone of the wild-type strain was isolated. Structural and functional analyses of an 8.0-kb region corresponding to the tagged site indicated the presence of two genes. One, designated AKT1, encodes a member of the class of carboxyl-activating enzymes. The other, AKT2, encodes a protein of unknown function. The essential roles of these two genes in both AK-toxin production and pathogenicity were confirmed by transformation-mediated gene disruption experiments. DNA gel blot analysis detected AKT1 and AKT2 homologues not only in the Japanese pear pathotype strains but also in strains from the tangerine and strawberry pathotypes. The host-specific toxins of these two pathotypes are similar in structure to AK-toxin. Homologues were not detected in other pathotypes or in non-pathogenic strains of A. alternata, suggesting acquisition of AKT1 and AKT2 by horizontal transfer.

Expression and physical association of Fc alpha receptor and Fc receptor gamma chain in human mesangial cells

BACKGROUND

Most intensive investigations on the pathogenesis of IgA nephropathy have focused on the process before IgA deposition and the characteristics of IgA/IgA immune complex (IgA IC), but it still remains uncertain whether mesangial IgA ICs may cause glomerular injuries directly or are only secondary events of another pathological process. To assess the role of IgA ICs in IgA nephropathy, we investigated the characteristics of Fc alpha receptor (Fc alphaR) and FcR gamma chain which is a signalling subunit of FcR in human mesangial cells (MCs).

METHODS

Gene expression of Fc alphaR and FcR gamma chain of human cultured MCs was examined by RT-PCR and subsequent Southern blot analyses. Sequence analyses after subcloning were also performed for further confirmation. Expression of Fc alphaR and FcR gamma chain at the protein level and their physical association in MCs were determined by immunoprecipitation after stimulation of the cells with heat-aggregated IgA.

RESULTS

Two distinct cDNA products were amplified from each cultured MC line. The sequence of the major product of approximately 900 bp was completely identical to that of Fc alphaR previously described. The smaller product had a 288 bp deletion which corresponded to exon 2 encoding the extracellular domain 2 of Fc alphaR. Gene expression of FcR gamma chain was also confirmed. Furthermore, we proved the physical association of Fc alphaR with the FcR gamma chain by co-immunoprecipitation under stimulation with a high dose of the heat-aggregated IgA.

CONCLUSION

These findings suggested that polymeric IgA and/or IgA IC can directly activate MCs via Fc alphaR associated with the gamma chain. Our data also indicated that phenotypic variations of Fc alphaR occur on MC, such as splicing forms, the chain association and/or the alpha chain expression itself, which may contribute to the pathogenesis of IgA nephropathy.

Control of acetic acid concentration by pH-stat continuous substrate feeding in heterotrophic culture phase of two-stage cultivation of Alcaligenes eutrophus for production of P(3HB) from CO2, H2, and O2 under non-explosive conditions

A-two stage culture method of hydrogen-oxidizing bacterium, Alcaligenes eutrophus, is used to produce poly-D-3-hydroxybutyrate, P(3HB) from CO2, O2, and H2 without using a very high oxygen transfer rate while maintaining the O2 concentration in gas phase below 6.9 (v/v)% to prevent detonation of the gas mixture. The two-stage method consists of a heterotrophic culture using fructose as carbon source for exponential cell growth and an autotrophic culture for P(3HB) accumulation. We investigated the use of acetic acid as a cheaper carbon source than fructose for the heterotrophic culture in the two-stage method. However, the acetate concentration in the culture system must be maintained at 1.0 g. dm-3 since its inhibitory effect on the cell growth is very strong. Then, high cell density cultivation of A. eutrophus was investigated by pH-stat continuous feeding of acetic acid to control acetate concentration. As a result, acetate concentration was automatically maintained around 1.0 g. dm-3 by using a feed with a composition in CH3COOH/CH3COONH4/KH2PO4 molar ratio of 5:1:0.084. Cell concentration increased to 48.6 g. dm-3 after 21 h of cultivation. The cell mass grown in the fed-batch culture on acetic acid was useful for P(3HB) production from CO2 in the subsequent autotrophic culture stage. Copyright 1999 John Wiley & Sons, Inc.

Optimization of l-lactic acid feeding for the production of poly-d-3-hydroxybutyric acid by Alcaligenes eutrophus in fed-batch culture

We investigated optimization of the feeding of L-lactic acid for the production of poly-D-3-hydroxybutyric acid [P(3HB)] by Alcaligenes eutrophus in a fed-batch culture system. An acidic substrate solution was fed automatically so as to maintain the pH of the culture liquid at 7.0. Feeding of a substrate solution containing 45% (w/v) L-lactic acid, 6.2% (w/v) sodium L-lactate, 5.8% (w/v) ammonia water and 1.8% (w/v) potassium phosphate [at a molar ratio of carbon to nitrogen (C/N molar ratio) of 10], allowed the L-lactate concentration in the culture liquid to be maintained at approximately 2 g/l and the cell concentration reached 27.4 g/l after 15 h of cultivation. To promote P(3HB) production, a two-stage fed-batch culture consisting of a culture for cell growth and one for P(3HB) accumulation was carried out. When the substrate solution, whose C N molar ratio was 23, was fed during the P(3HB) accumulation phase, the cell concentration and the P(3HB) content in the cells reached 103 g/l and 57.6% (w/w), respectively, in 51.5 h.

Targeted disruption of a melanin biosynthesis gene affects conidial development and UV tolerance in the Japanese pear pathotype of Alternaria alternata

Structural analysis of the BRM2 gene involved in melanin biosynthesis of the Japanese pear pathotype of Alternaria alternata suggested that this gene encodes 1,3,8-trihydroxynaphthalene reductase. Targeted disruption of the BRM2 gene did not affect pathogenicity, vegetative growth, or the number of conidia produced. Targeted disruption, however, did reduce conidial size and septal number, suggesting that melanin is associated with conidial development. The conidia of brm2 mutant transformants were more sensitive to UV light than those of the wild type, demonstrating that melanin confers UV tolerance.