Structure-activity relationship of HP (2–20) analog peptide: Enhanced antimicrobial activity by N-terminal random coil region deletion

Park, Yoonkyung,Park, Seong-Cheol,Park, Hae-Kyun,Shin, Song Yub,Kim, Yangmee,Hahm, Kyung-Soo John Wiley & Sons, etc 2007 Biopolymers Vol.88 No.2

<P>HP (2–20) (AKKVFKRLEKLFSKIQNDK) is a 19-aa antimicrobial peptide derived from N-terminus of Helicobacter pylori Ribosomal protein L1 (RpL1). In the previous study, several analogs with amino acid substitutions were designed to increase or decrease only the net hydrophobicity. In particular, substitutions of Gln<SUP>16</SUP> and Asp<SUP>18</SUP> with Trp (Anal 3) for hydrophobic amino acid caused a dramatic increase in antibiotic activity without a hemolytic effect. HP-A3 is a potent antimicrobial peptide that forms, in a hydrophobic medium, an amphipathic structure consisting of an N-terminal random coil region (residues 2–5) and extended C-terminal regular α-helical region (residues 6–20). To obtain the short and potent α-helical antimicrobial peptide, we synthesized a N-terminal random coil deleted HP-A3 (A3-NT) and examined their antimicrobial activity and mechanism of action. The resulting 15mer peptide showed increased antibacterial and antifungal activity to 2- and 4-fold, respectively, without hemolysis. Confocal fluorescence microscopy studies showed that A3-NT was accumulated in the plasma membrane. Flow cytometric analysis revealed that A3-NT acted in salt- and energy-independent manner. Furthermore, A3-NT causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy. Circular dichroism (CD) analysis revealed that A3-NT showed higher α-helical contents than the HP-A3 peptide in 50% TFE solution. Therefore, the cell-lytic efficiency of HP-A3, which depended on the α-helical content of peptide, correlated linearly with their antimicrobial potency. © 2007 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 88: 199–207, 2007.</P><P>This article was originally published online as an accepted preprint. The ‘Published Online’ date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com</P>

The Effect of the Recombinant Human Interleukin-2 Gene in Potato : Solanum tuberosum cv. Superior

Park, Yoonkyung,Cheong, Hyeonsook 한국식물학회 2001 Journal of Plant Biology Vol.44 No.4

To examine the effect of the T-cell growth factor (human interleukin-2), we constructed a binary vector, pSSK-1, carrying the recombinant human interleukin-2 (rhlL-2) gene, and transferred it into Agrobacterium tumefaciens. Using this construct, we then transformed potato explants (Solanum tuberosum cv. Superior), achieving 100% regeneration of shoots on a modified MS medium. Of the putative transformed shoots, 81% rooted and were selected on 200㎎/L kanamycin. Both Southern and northern analyses verified the transformation events. An ELISA test also indicated that the rhIL-2 protein was produced from rhIL-2-transformed potatoes. To determine whether this protein was biologically active in the potato cells, we performed a biological assay using the IL-2 dependent cell line, CTLL-2. The suspension containing extract from the transformants showed significant proliferation of the IL-2 dependent CTLL-2 cells, whereas cells did not proliferate in the nontransformed potato. We then grew the verified rhlL-2 transgenic potatoes in soil, and compared their performance with that of nontransgenic potatoes as well as those that had been transformed with GUS. Growth rates, as calculated from plant heights, were up to 50% higher than for either the nontransgenic or the GUS-transformed potatoes. Similar patterns were found with Arabidopsis thaliana plants treated in the same manner. All of these results suggest that rhIL-2 may function as a growth factor in potato.

Vector Construction for the Tissue Specific Expression and Production of IL-2 Gene in Potato : Solanum tuberosum cv. Superior

Park, Yoonkyung,Cheong, Hyeonsook 조선대학교 기초과학연구소 1997 自然科學硏究 Vol.20 No.1

We constucted two expression vetors, pSSK-1 and pSSK-6, carrying IL-2 gene for the purpose of estimating the amount of its products and the effects in the potato. The pSSK-6 is under the control of 35S CaMV promoter(pSSK-1) specifically expressed in potato tuber. Also, pSSK-1, a binary vector carrying interleukin-2 (IL-2) gene, was constructed to be examine the possibility of the production of IL-2 and its effects in potato, and transferred into A. tumefaciens for the sake of the transformation of potato (solanum tuberosum cv. Superior). In our recent work, we verified that IL-2 gene from pSSK-1 vector was expressed in all parts of the transformed potato plant. However the amount of IL-2 protein was estimated very little.

Transformation of Arabidipsis thaliana using root explants

Park, Yoonkyung,Cheong, Hyeonsook 조선대학교 부설생명과학 연구소 1998 생명과학 연구 Vol.6 No.-

The IL-2 gene is under the control of 35S CaMV promoter which makes its following gene to be expressed in whole plant. We constructed pSSK-1 carrying interleukin-2 gene to examine the IL-2 productivity and effects in Arabidopsis thaliana, and transferred into A. tumefaciens for the sake of the transformation of Arabidopsis ecotype C_(24). We used a simple and highly reproducible tissue-culture procedure to transform Arabidopsis with Agrobacterium tumefaciens as the gene delivery system and the roots of axenically grown plants as the explant source. Root segments were placed onto solidfied CIM (0.5 mg/L 2,4-D, 0.05 mg/L kinetin) medium in a petridish for 2 days, and transferred to solidfied SIM (5 mg/L 2IP, 0.15 mg/L IAA, 50mg/L kanamycin, 750 mg/L vancomycin) medium. Shoots were intermittently appeared from the green calli over the next several weeks.

Quantitative Correlation between Carrier Mobility and Intermolecular Center-to-Center Distance in Organic Single Crystals

Park, Yoonkyung,Park, Kyung Sun,Jun, Byeongsun,Lee, Yong-Eun Koo,Lee, Sang Uck,Sung, Myung Mo American Chemical Society 2017 Chemistry of materials Vol.29 No.9

<P>Charge transport properties of organic semiconductors critically depend on their molecular packing structures. Controlling the charge transport by varying the molecular packing and understanding their structure property correlations are essential for developing high-performance organic electronic devices. Here, we demonstrate that the charge carrier mobility in organic single-crystal nanowires can be modulated with respect to the intermolecular center-to-center distance by applying uniaxial strain to the cofacially stacked crystals. Monotonic changes in charge carrier mobility (from 0.0196 to 19.6 cm(2)V(-1)s(-1) for 6,13-bis(triisopropylsilylethylnyl) pentacene (TIPS-PEN)) were observed under a wide range of strains from 16.7% (compressive) to 16.7% (tensile). Furthermore, the measured values of charge carrier mobility were in good agreement with theoretical calculations based on charge localized hopping theory. These results provide a definitive relationship between intermolecular packing arrangement and charge transports, which enables a huge improvement in charge carrier mobility for organic single-crystal materials.</P>

Transformation of Arabidopsis thaliana using root explants

Park, Yoonkyung,Cheong, Hyeonsook 조선대학교 생명과학연구소 1998 생명과학 연구 Vol.6 No.-

The IL-2 gene is under the control of 35S CaMV promoter which makes its following gene to be expressed in whole plant. We constructed pSSK-1 carrying interleukin-2 gene to examine the IL-2 productivity and effects in Arabidopsis thaliana, and transferred into A. tumefaciens for the sake of the transformation of Arabidopsis ecotype C_(24). We used a simple and highly reproducible tissue-culture procedure to transform Arabidopsis with Agrobacterium tumefaciens as the gene delivery system and the roots of axenically grown plants as the explant source. Root segments were placed onto solidfied CIM (0.5 ㎎/L 2,4-D, 0.05 ㎎/L kinetin) medium in a petridish for 2 days, and transferred to solidfied SIM (5 ㎎/L 2IP, 0.15 ㎎/L IAA, 50 ㎎/L kanamycin, 750 ㎎./L vancomycin) medium. Shoots were intermittently appeared from the green calli over the next several weeks.

Study of antimicrobial activity and the mode of action of Anal P5 peptide

Park, Yoonkyung,Hahm, Kyung-Soo The Basic Science Institute Chosun University 2008 조선자연과학논문집 Vol.1 No.1

In a previous study, we showed that Cecropin A (1-8)-Magainin 2 (1-12) hybrid peptide (CA-MA)'s analogue, Anal P5, exhibit broad-spectrum antimicrobial activity. Anal P5, designed by flexible region (positions 9, 10)-substitution, Lys- (positions 4, 8, 14, 15) and Leu- (positions 5, 6, 12, 13, 16, 17, 20) substitutions, showed an enhanced antimicrobial and antitumor activity without hemolysis. The primary objective of the present study was to gain insight into the relevant mechanisms of antimicrobial activities of Anal P5 by using flow cytometric analysis. Anal P5 exhibits strong antifungal activity in a salt concentration independent manner. In addition, Anal P5 causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy, supporting its antibacterial activity. Its potent antibiotic activity suggests that Anal P5 is an excellent candidate as a lead compound for the development of novel antibiotic agents.

Perioperative outcomes of sinusoidal obstruction syndrome underwent liver resection for colorectal metastases after neoadjuvant chemotherapy

Yoonkyung WOO,Yoonyoung CHOI,Haneol PARK,Chang Ho SEO,Sung Eun PARK,Joseph AHN,Ho Joong CHOI,Tae Ho HONG,Young Kyoung YOU 한국간담췌외과학회 2022 Annals of hepato-biliary-pancreatic surgery Vol.26 No.-

Urban debris flow vulnerability map: an application to the metropolitan cities in Korea

Park, Yoonkyung,Kim, Sangdan,Joo, Jingul,Kim, Hayong,Jeong, Sangman,Kim, Hyun-Ki Desalination Publications 2018 Desalination and water treatment Vol.109 No.-

Future Changes of Stream Flow and Water Quality in the Byongseong Stream Watershed under Multiple Future Climate Scenarios

Park, Yoonkyung,Lee, Jeonghoon,Choi, Daegyu,Kim, Sangdan Korean Society of Hazard Mitigation 2015 한국방재학회논문집 Vol.15 No.2

본 연구에서는 4개의 GCMs(General Circulation Models)에서부터 생산된 미래 기후 자료를 이용하여 유역 스케일에서 하천유량과 하천수질이 미래에 어떻게 변화하는지를 파악하고자 하였다. 이를 위하여 하천 유량과 수질자료(부유물질, 총 질소)는 강수량과 기온의 함수로 표현하였으며, 대상 유역의 미래 기후 자료와의 관계식이 도출된다. 미래 기후자료는 편의보정을 통해서 계산되며, 이러한 자료는 미래의 하천 유량과 수질을 예측하기 위하여 앞서 도출된 관계식에 적용된다. 본 연구에서 사용된 GCMs는 CNCM3, CSMK3, CGHR, MPEH5으로 총 4가지이며 각각의 모델은 다시 A2, A1b, B1 SRES 시나리오로 세분화되어지므로 총 12개의 시나리오가 검토되었다. A2 시나리오에서 미래 강수량과 기온은 크게 증가하였다. 이 중 기온은 대체적으로 증가하는 경향성을 보이고 있으며, 비교적 먼 미래로 갈수록 그 증가정도가 두드러지게 나타났다. 강수량의 경우 평균적인 양은 증가하지만 편차가 크게 나타남을 확인하였다. 대부분의 시나리오에서 현재에 비해 미래의 하천 유량과 수질이 증가하는 것으로 보이고 있으나, 변동정도는 작은 것으로 나타났다. GCMs에 따른 변화를 살펴보면, MPEH5와 CGHR에서는 미래의 하천 유량과 수질이 크게 증가하는 것으로 나타났으나 그에 비해 CSMK3와 CNCM3의 증가폭은 비교적 작았다. 이러한 변동성을 기간별로 살펴보면, 현재와 비교적 가까운 미래인 2011년부터 2040년까지의 기간에서는 하천 유량과 수질은 현재와 비슷하거나 약간 감소하는 경향을 보였다. 2041년부터 2070년까지의 기간에서 하천 유량과 수질은 현재에 비해 감소하고, 비교적 먼 미래인 2071년부터 2100년까지의 기간에서는 유량과 수질의 값이 현재에 비해 커지는 경향을 보였다. 대부분의 미래 시나리오는 SRES 시나리오와 유사한 추세를 가지는 것으로 나타났지만, 시나리오 간의 미래 예측 결과는 큰 차이가 있는 것으로 나타났다. This study attempts to grasp future changes in watershed scale stream flow and water quality using the future climate data from four general circulation models (GCMs). To this end, stream flow and water quality data (suspended solid and total nitrogen) were expressed as functions of precipitation and temperature to establish the relationships between those values and the future climate data for the watershed. This data was calculated through a bias correction method and was then substituted into functions that predict future stream flow and water qualities. A total of four GCMs including CNCM3, CSMK3, CGHR and MPEH5 were used, each of them included A2, A1B and B1 SRES scenarios, for a total of 12 scenarios reviewed. The future precipitation and temperature of A2 scenario showed the greatest increase. Temperature had shown an increasing trend that became more prominent in the far future, while precipitation increased in average amounts but with large deviations. Although future stream flow and water quality was increased in most of the scenarios compared to those of the present, the variability was shown to be much smaller than the present. MPEH5 and CGHR showed large increases in future stream flow and water quality, while CSMK3 and CNCM3 showed smaller. The changes were reviewed by period, and the results showed similar or slightly decreased flow and water qualities values compared to the present for 2011 to 2040, decreased values for 2041 to 2070 and increased values for 2071 to 2100. There were also large differences in future predictions among the scenarios, although it could be identified that most of the future scenarios had trends similar to the SRES scenarios.