• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.168-172
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• 2006

In this study. the transcriptional features of a 2.8 kb region spanning the sigH and rplA genes of Bacillus subtilis were clarified using synthetic oligonucleotides complementary to the transcripts of the rpmG, secE, nusG, and rplK genes. The 5' ends of three transcripts corresponding to this region were located and mapped on the chromosome via primer extension analysis. Three regions, designated Prg, Pn, and Prk, which partially share the consensus sequence recognized by ${\sigma}^A$ RNA polymerase, were theorized to function as promoter elements. The rpmG and secE genes of B. subtilis were cotranscribed from the designated prg promoter, whereas the nusG and rplK genes were transcribed separately from the Pn and Prk promoters, respectively. Accordingly, the transcriptional features, as well as the gene organization, of the region encompassing the sigH and rplA genes of B. subtilis, including the rpmG-secE-nusG-rplK genes, were determined to be distinct from those of Escherichia coli. Divergences in terms of gene organization and transcriptional features within the relevant region would serve as excellent criteria for the delineation of phylogenetic relationships among bacteria.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.253-257
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• 1997

The secE gene of Streptomyces lividans TK24 was cloned by the polymerase chain reaction method with synthetic oligonucleo- tide primers designed on the basis of the nucleotide sequences of Streptomyces coelicolor secE-nusG-rplK operon. The deduced amino acid sequences of the SecE were highly homologous to those of other known SecE protein, that is 36.8%, 30.4%, 80.0%, and 80.9%, similarity to E. coli, Bacillus subtilis, Streptomyces griseus, Streptomyces virginiae SecE, respectively and exactly same with Streptomyces coelicolor SecE. It means that in spite of evolutionary differences, the genes for protein translocation machinery are highly conserved in eubacteria. The gene organization of secE-nusG-rplK is also similar to that of E. coli, B. subtilis, and streptomycetes.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.17 no.6
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• pp.708-716
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• 1988

Local heat transfer coefficients were measured on semi-cylinders on which a circular water jet impinged in crossflow. The ratio of the semi-cylinder's diameter and the nozzle outlet diameter were varied parametrically, as were the Reynolds number and the supplementary water heights. The measurements showed that the circumferential distribution of the heat transfer coefficient peaked at the stagnation point. For a fixed supplementary water height, the peak heat transfer coefficient was not depend on the curvature of test specimen(d/D). Optimum height of supplementary water which brought about the augmentation of heat transfer at the stagnation point was S/D=1. The Nusselt number decreased as the circumferential distance or angle increased. The circumferential distribution of dimensionless heat transfer (Nu/Nus) was independent of d/D ($d/D{\geq}8.33$), but for the d/D<8.33, it was depended on d/D. At a fixed angle of specimen, dimensionless heat transfer (Nu/Nus) decreased as the ratio d/D increased. The extent of the decrease between d/D=6.67 and 8.33 was markedly greater than that between d/D=8.33 and 10, or d/D=10 and 11.67.

• STI Policy Review
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• v.8 no.1
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• pp.1-22
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• 2017

There has been a pronounced increase in research and development (R&D) expenditure in Singapore over the last two decades, with government spending accounting for a sizeable share. This increase has been spurred by public policy emphasis on research and innovation as engines of economic growth. This paper analyses the impact of R&D on economic performance in Singapore from 1978 to 2012 through the use of time series analysis. The Cobb-Douglas based analysis shows a long-run equilibrium relationship between Total Factor Productivity (TFP) and R&D investments. We found that the short-run productivity of R&D in Singapore is comparable to smaller advanced economies in the Organisation for Economic Co-operation and Development (OECD). However, in terms of long-run R&D productivity, Singapore lags slightly behind the smaller OECD nations and far behind the G7 countries. This suggests leakage of value capture and low absorptive capacity in local firms. Possibility of productivity improvements induced by policy changes in the 1990s was considered, but no evidence of significant structural breaks was found. Lastly, Granger causality analysis reveals that public sector R&D augments private sector R&D capital, thus playing an important role in generating externalities and spillover effects. Policy implications and lessons for other middle-income countries are discussed.

• The Microorganisms and Industry
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• v.18 no.3
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• pp.69-74
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• 1992

최근 Okamoto등(18)이 처음으로 VB receptor 유전자인 vbr A의 cloning 및 vbr A의 E. coli 유래의 필수 유전자인 Nus G와의 높은 상동성(36%)으로부터 전사, 번역기구의 필수 유전자로서 가능성의 보고와, Miyake등(19)은 A-factor receptor의 repressor로서의 기능을 보고함에 따라 이들 자기조절인자의 항생물질등 2차 대사산물의 생합성에 있어서 signal전달에 따른 전사조절의 switch on-off 기구 연구에 박차를 가하에 되었으며 본고에서는 VB를 중심으로한 유도인자의 기능면 및 응용면을 소개하고자 한다.

• Journal of Microbiology and Biotechnology
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• v.18 no.3
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• pp.483-489
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• 2008

Nine newly isolated mushroom strains were tested to assess both their zinc tolerance and potential for zinc removal from an aqueous solution. Four strains of ectomycorrhizal fungi, namely Clavariadelphus truncatus (T 192), Rhizopogon roseolus (T 21), Lepista nuda (T 373), and Tricholoma equestre (T 174), along with five strains of white rot fungi, Lenzites betulina (S 2), Trametes hirsuta (T 587), Ganoderma spp. (T 99), Polyporus arcularius (T 438), and Ganoderma carnosum (M 88), were investigated using zinc-amended solid and liquid media. Their biosorption properties were also determined. The colony diameter and dry weight were used as tolerance indices for fungal growth. C. truncatus and T. equestre were not strongly inhibited at the highest concentrations of (225 mg/l) zinc in solid media. The most tolerant four strains with solid media, C. truncatus, G carnosum, T. hirsuta, and T. equestre, were then chosen for tolerance tests in liquid media. An ectomycorrhizal strain, C. truncatus, was also detected as the most tolerant strain in liquid media. However, the metal-tolerant strains demonstrated weak activity in the biosorption studies. In contrast, the highest biosorption activity was presented by a more sensitive strain, G. carnosum. In addition, seven different biosorbent types from G. carnosum (M 88) were compared for their Zn (II) biosorption in batch experiments.