Because the phosphoenolpyruvate:sugar phosphotransferase system plays multiple regulatory roles in addition to the phosphorylation-coupled transport of many sugars in bacteria, synthesis of its protein components is regulated in a highly sophisticated way. Thus far, the cAMP receptor protein (CRP) complex and Mlc are known to be the major regulators of ptsHIcrr and ptsG expression in response to the availability of carbon sources. In this report, we performed ligand fishing experiments by using the promoters of ptsHIcrr and ptsG as bait to find out new factors involved in the transcriptional regulation of the phosphoenolpyruvate:sugar phosphotransferase system in Escherichia coli, and we found that the anaerobic regulator ArcA specifically binds to the promoters. Deletion of the arcA gene caused about a 2-fold increase in the ptsG expression, and overexpression of ArcA significantly decreased glucose consumption. In vitro transcription assays showed that phospho-ArcA (ArcA-P) represses ptsG P1 transcription. DNase I footprinting experiments revealed that ArcA-P binds to three sites upstream of the ptsG P1 promoter, two of which overlap the CRP-binding sites, and the ArcA-P binding decreases the CRP binding that is essential for the ptsG P1 transcription. These results suggest that the response regulator ArcA regulates expression of enzyme IICB Glc mediating the first step of glucose metabolism in response to the redox conditions of growth in E. coli.The bacterial phosphoenolpyruvate:sugar phosphotransferase system (PTS) 1 consists of two general cytoplasmic proteins, enzyme I and histidine phosphocarrier protein HPr, and some sugar-specific components collectively known as enzyme II (1, 2). Glucose-specific enzyme II of Escherichia coli consists of two subunits, soluble enzyme IIA Glc (EIIA Glc ) and membrane-bound enzyme IICB Glc . Thus, glucose transport in E. coli involves three soluble PTS components (enzyme I, HPr, and EIIA Glc , encoded by the ptsHIcrr operon) and one membranebound protein, enzyme IICB Glc (EIICB Glc ), encoded by the ptsG gene. During translocation of glucose, a phosphoryl group derived from phosphoenolpyruvate is transferred sequentially along a series of proteins to the transported glucose molecule, eventually converting it into glucose 6-phosphate. The sequence of phosphotransfer is from phosphoenolpyruvate to the general PTS proteins enzyme I and HPr and further to the carbohydrate-specific cytoplasmic EIIA Glc , membrane-bound EIICB Glc , and glucose.The PTS takes an important part in metabolic adaptation to environmental changes to compete effectively with ambient organisms by sensing the availability of nutrients in the environment. In addition to sugar transport, multiple roles are exerted by the PTS and these include chemoreception (3), catabolite repression (4), carbohydrate transport and metabolism (1, 5, 6), carbon storage (7,8), and the coordination of carbon and nitrogen metabolism (9). More recently, we found that EIIA Glc of the PTS also regulates the flux between respirat...

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Multi-layered material (sandwich panel) consists of double-sided steel plate which is incombustible material or similar material and core material which is not incombustible material. In case of sandwich panel which uses combustible material as insulation, flames spread inside the steel plate at the time of fire so that it is difficult to extinguish fire from the outside and flames spread rapidly and may cause the building to collapse. The current Building Act requires the sandwich panel to secure fire-retardant performance according to the purpose and size of building. In this study, the fire spreading prevention structure applied to partial exterior walls was applied to multi-layered material and its effect was measured through full scale fire test and the possibility to secure fire safety of buildings by applying the fire spreading prevention structure to multi-layered material in future was presented.

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Background As the misuse and abuse of medical narcotics are increasing in South Korea, an information system for the integrated information management of medical narcotic drugs across the nation is needed. This paper presents the development process of the Narcotics Information Management System (NIMS) for the monitoring of medical narcotics usage and the results of its implementation. Methods As the NIMS enforces that all narcotics handlers digitally report all information on handling medical narcotic drugs, the functional requirements of the NIMS have been identified in accordance with the Narcotics Control Act. In addition to the functional requirements, the non-functional requirements of the NIMS have been elicited by major narcotics handlers and their associations. The non-functional requirements include privacy, availability, connectivity, interoperability, and data integrity. The system design with entity-relationship diagrams and its implementation processes have been presented. Results The NIMS encompasses all narcotic handlers, which comprise exporting, importing, and pharmaceutical companies; wholesalers; hospitals and clinics; and pharmacies, collecting over 120 million cases annually. It enables transparent monitoring throughout the life cycle, from manufacturing, sales, purchase, and disposal of narcotics. As a result, the number of prescriptions for medical narcotics has been reduced by 9.2%. Conclusions To the best of our knowledge, the NIMS is the world's first system to manage all information on the total life cycle of medical narcotics, including imports, production, distribution, use, and disposal of drugs. This system has enabled the safety management and monitoring of medical narcotic drugs. Additionally, it provides consistent and transparent information to physicians and patients, leading to the autonomous safety management of narcotics. The successful development of the NIMS can provide guidelines for implementing a narcotics management system in other countries.