• 제목/요약/키워드: Systems Biotechnology

검색결과 1,493건 처리시간 0.023초

Antifungal Mechanism of Action of Lauryl Betaine Against Skin-Associated Fungus Malassezia restricta

  • Do, Eunsoo;Lee, Hyun Gee;Park, Minji;Cho, Yong-Joon;Kim, Dong Hyeun;Park, Se-Ho;Eun, Daekyung;Park, Taehun;An, Susun;Jung, Won Hee
    • Mycobiology
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    • 제47권2호
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    • pp.242-249
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    • 2019
  • Betaine derivatives are considered major ingredients of shampoos and are commonly used as antistatic and viscosity-increasing agents. Several studies have also suggested that betaine derivatives can be used as antimicrobial agents. However, the antifungal activity and mechanism of action of betaine derivatives have not yet been fully understood. In this study, we investigated the antifungal activity of six betaine derivatives against Malassezia restricta, which is the most frequently isolated fungus from the human skin and is implicated in the development of dandruff. We found that, among the six betaine derivatives, lauryl betaine showed the most potent antifungal activity. The mechanism of action of lauryl betaine was studied mainly using another phylogenetically close model fungal organism, Cryptococcus neoformans, because of a lack of available genetic manipulation and functional genomics tools for M. restricta. Our genome-wide reverse genetic screening method using the C. neoformans gene deletion mutant library showed that the mutants with mutations in genes for cell membrane synthesis and integrity, particularly ergosterol synthesis, are highly sensitive to lauryl betaine. Furthermore, transcriptome changes in both C. neoformans and M. restricta cells grown in the presence of lauryl betaine were analyzed and the results indicated that the compound mainly affected cell membrane synthesis, particularly ergosterol synthesis. Overall, our data demonstrated that lauryl betaine influences ergosterol synthesis in C. neoformans and that the compound exerts a similar mechanism of action on M. restricta.

Roles of the Peptide Transport Systems and Aminopeptidase PepA in Peptide Assimilation by Helicobacter pylori

  • Ki, Mi Ran;Lee, Ji Hyun;Yun, Soon Kyu;Choi, Kyung Min;Hwang, Se Young
    • Journal of Microbiology and Biotechnology
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    • 제25권10호
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    • pp.1629-1633
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    • 2015
  • Peptide assimilation in Helicobacter pylori necessitates a coordinated working of the peptide transport systems (PepTs) and aminopeptidase (PepA). We found that H. pylori hydrolyzes two detector peptides, L-phenylalanyl- L-3-thiaphenylalanine (PSP) and L-phenylalanyl- L-2-sulfanilylglycine (PSG), primarily before intake and excludes their antibacterial effects, whereas Escherichia coli readily transports them with resultant growth inhibition. PSP assimilation by H. pylori was inhibited by aminopeptidase inhibitor bestatin, but not by dialanine or cyanide-m-chlorophenylhydrazone, contrary to that of E. coli. RT- and qRT-PCR analyses showed that H. pylori may express first the PepTs (e.g., DppA and DppB) and then PepA. In addition, western blot analysis of PepA suggested that the bacterium secretes PepA in response to specific inducers.

감미단백질 모넬린 발현 딸기 형질전환 식물체 개발 (Development of transgenic strawberry plants expressing monellin, a sweet protein)

  • 민성란;고석민;유재일;박지현;이소영;이인하;김현숙;김태일;최필선;정원중;김석원;김종현;유장렬
    • Journal of Plant Biotechnology
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    • 제42권3호
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    • pp.180-185
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    • 2015
  • '여봉'과 '매향' 딸기 식물체로부터 잎 절편을 형질전환 재료로 이용하였다. CaMV 35S promoter에 모넬린 유전자가 연결된 pGA482-pS1D 벡터가 들어있는 아그로박테리움 EHA105 균주를 매개로 형질전환을 수행하였다. 공동 배양 후 잎 절편체로부터 캘러스 형성과 식물체 재분화율은 '여봉' 품종이 '매향' 품종보다 높았으며 이들 형질전환 식물체는 정상적으로 생육하여 개화하였다. PCR 및 Southern blot 분석을 통해 1-2 카피의 모넬린 유전자가 형질전환 딸기 식물체에 도입되었음을 확인하였으며, Northern blot 분석을 통하여 두 품종에서 모두 모넬린 유전자가 발현됨을 확인하였다. 비록 장기간 계대배양된 이들 딸기 형질전환 식물체에서는 모넬린 유전자가 escape 되는 경향을 보였지만, 본 연구에서 확립된 형질전환 시스템은 딸기의 유전적 개량을 위한 새로운 기회를 제공할 수 있을 것이다.

Variations in Protein Glycosylation in Hansenula polymorpha Depending on Cell Culture Stage

  • Kim, So-Young;Sohn, Jung-Hoon;Pyun, Yu-Ryang;Choi, Eui-Sung
    • Journal of Microbiology and Biotechnology
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    • 제17권12호
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    • pp.1949-1954
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    • 2007
  • A simple way to prevent protein hyperglycosylation in Hansenula polymorpha was found. When glucose oxidase from Aspergillus niger and carboxymethyl cellulase from Bacillus subtilis were expressed under the control of an inducible methanol oxidase (MOX) promoter using methanol as a carbon source, hyperglycosylated forms occurred. In contrast, MOX-repressing carbon sources (e.g., glucose, sorbitol, and glycerol) greatly reduced the extent of hyperglycosylation. Carbon source starvation of the cells also reduced the level of glycosylation, which was reversed to hyperglycosylation by the resumption of cell growth. It was concluded that the proteins expressed under actively growing conditions are produced as hyperglycosylated forms, whereas those under slow or nongrowing conditions are as short-glycosylated forms. The prevention of hyperglycosylation in the Hansenula polymorpha expression system constitutes an additional advantage over the traditional Saccharomyces cerevisiae system in recombinant production of glycosylated proteins.

인체 락토페린 생산 형질전환 고구마 개발 (Development of transgenic sweet potato producing human lactoferrin)

  • 민성란;김재화;정원중;이영복;유장렬
    • Journal of Plant Biotechnology
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    • 제36권3호
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    • pp.224-229
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    • 2009
  • Human lactoferrin is an iron-binding glycoprotein with many biological activities, including the protection against microbial and virus infection and stimulation of the immune system. We introduced a human lactoferrin (hLf) cDNA under the control of 35S promoter into sweet potato by particle bombardment. Transgenic plants were regenerated via somatic embryogenesis. Transgenic plants were produced typical tuberous roots in soil. PCR, Southern and northern analyses confirmed that the hLf cDNA was incorporated into the plant genome and was properly expressed in plants. Western blot analysis showed that the 80 kDa full length hLf protein was produced in transgenic tuberous roots. Overall results indicated that sweet potato would be an excellent host to produce human therapeutic proteins.