• Journal of Microbiology and Biotechnology
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• 제16권9호
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• pp.1422-1428
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• 2006

An ABC transporter apparatus of the Gram-negative bacterial type I secretion pathway can be used as a secretory protein expression system in Escherichia coli. Four types of coexpression systems for the Pseudomonas fluorescens lipase gene, tliA, and its cognate ABC transporter gene cluster, tliDEF, were constructed. When the relative expression levels were changed by adding different concentrations of IPTG, the secretion (16.9 U/ml of culture) of TliA in E. coli [pTliDEFA-223+pACYC184] was significantly higher than E. coli [pKK223-3+pTliDEFA-184] secreting the lowest level of TliA (5.2 U/ml of culture). Maximal accumulation of the lipase secreted occurred in the mid-exponential phase, implying that the efficient protein secretion via an ABC transporter was restricted only to actively growing cells. Finally, the secretion level of TliA in E. coli [pTliDEFA-223+pACYC184] was increased to 26.4 U/ml by inducing gene expression at the culture initiation time. These results indicate that a significant increase in the ABC transporter-dependent protein secretion can be achieved by simply controlling the relative expression levels between the ABC transporter and its passenger protein, even in the recombinant E. coli cells.

• The Plant Pathology Journal
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• 제30권4호
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• pp.375-383
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• 2014

Fungi tolerate exposure to various abiotic stresses, including cytotoxic compounds and fungicides, via their ATP-driven efflux pumps belonging to ATP-binding cassette (ABC) transporters. To clarify the molecular basis of interaction between the fungus and various abiotic stresses including fungicides, we constructed a cDNA library from germinated conidia of Colletotrichum acutatum, a major anthracnose pathogen of pepper (Capsicum annum L.). Over 1,000 cDNA clones were sequenced, of which single clone exhibited significant nucleotide sequence homology to ABC transporter genes. We isolated three fosmid clones containing the C. acutatum ABC1 (CaABC1) gene in full-length from genomic DNA library screening. The CaABC1 gene consists of 4,059 bp transcript, predicting a 1,353-aa protein. The gene contains the typical ABC signature and Walker A and B motifs. The 5'-flanking region contains a CAAT motif, a TATA box, and a Kozak region. Phylogenetic and structural analysis suggested that the CaABC1 is a typical ABC transporter gene highly conserved in various fungal species, as well as in Chromista, Metazoans, and Viridiplantae. We also found that CaABC1 was up-regulated during conidiation and a minimal medium condition. Moreover, CaABC1 was induced in iprobenfos, kresoxim-methyl, thiophanate-methyl, and hygromycin B. These results demonstrate that CaABC1 is necessary for conidiation, abiotic stress, and various fungicide resistances. These results will provide the basis for further study on the function of ABC transporter genes in C. acutatum.

• 생명과학회지
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• 제20권2호
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• pp.176-182
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• 2010

벼의 생산에 있어 가장 큰 문제 요인 중 하나인 벼도열병의 발생 원인균인 벼도열병균은 다양한 기작에 의해 방제 약제에 대한 내성을 가지는 것으로 알려져 있다. 막 운반단백질인 ABC transporter의 경우 환경으로부터의 다양한 독성 물질들을 배출하는 것으로 알려져 있다. 이미 알려진 벼도열병균의 게놈 서열로부터 생물정보학적 분석을 통하여 ABC transporter 단백질의 도메인 특성을 보이는 33개의 유전자군 서열을 예측하였다. 이중 3개의 경우는 이미 알려진 유전자로 판명되었다. Southern Hybridization 분석에 적용한 20개의 유전자들이 모두 게놈상에 단일 copy로 존재함을 확인하였다. 새로 예측된 30개의 유전자중 11개는 RT-PCR을 통하여 전사단계에서의 유전자 발현이 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제14권3호
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• pp.635-638
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• 2004

An ATP-binding-cassette (ABC) transporter gene in the cephabacin biosynthetic gene cluster of Lysobacter lactamgenus was characterized. The amplified orf10 (cpbJ) gene was subcloned into pET-28a(+) vector and expressed in E. coli BL21(DE3) strain by 0.5 mM IPTG at $30^{\circ}C$. The membrane fraction of recombinant E. coli cells was separated by ultracentrifugation, and solubilized using 2.5% octyl-$\beta$-D-glucoside. Using the solubilized membrane fraction, the artificial proteoliposomes were reconstituted and analyzed for the biological activity of CpbJ protein. Upon measuring ATPase activity, the proteoliposome made from recombinant E. coli membrane proteins showed slightly higher activity than that from host E. coli membrane proteins. In the measurement of membrane transport activity, the reconstituted proteoliposome of recombinant E. coli membrane proteins exhibited higher activity when both substrates of cephalosporin C and L-Ala-L-Ser were applied, compared to the case of cephalosporin C or L-Ala-L-Ser only. It implies that the CpbJ protein is an ABC transporter secreting cephabacin antibiotics synthesized in cytoplasm.

• 한국자원식물학회지
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• 제22권3호
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• pp.273-280
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• 2009

A cDNA clone encoding a MDR-like ABC transporter protein was isolated from Brassica rapa seedlings, through rapid amplification of cDNA ends (RACE). This gene (named as Brmdr 1; GenBank accession no.: DQ296184 ) had a total length of 4222 bp with an open reading frame of 3900 bp, and encoded a predicted polypeptide of 1300 amino acids with a molecular weight of 143.1 kDa. The BrMDR1 protein shared 71.0, 62.5, 60.0 and 58.2% identity with other MDR proteins isolated from Arabidopsis thaliana (AAN28720), Coptis japonica (CjMDR), Gossypium hirsutum (GhMDR) and Triticum aestivum (TaMDR) at amino acid level, respectively. Southern blot analysis showed that Brmdr1 was a low-copy gene. Expression pattern analysis revealed that Brmdr1 constitutively expressed in the root, stem petals and stamens, but with lower expression in leaves and open flowers. The domains analysis showed that BrMDR1 protein possessed two transmembrane domains (TMDs) and two nucleotide binding domains (NBDs) arranging in "TMD1-NBD1-TMD2-NBD2" direction, which is consistent with other MDR transporters. Within NBDs three characteristic motifs common to all ABC transporters, "Walker A", "Walker B" and C motif, were found. These results indicate that BrMDR1 is a MDR-like ABC transporter protein that may be involved in the transport and accumulation of secondary metabolites.

• Parasites, Hosts and Diseases
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• 제53권3호
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• pp.335-339
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• 2015

Cryptosporidium andersoni ATP-binding cassette (CaABC) is an important membrane protein involved in substrate transport across the membrane. In this research, the nucleotide binding domain (NBD) of CaABC gene was amplified by PCR, and the eukaryotic expression vector of pEGFP-C1-CaNBD was reconstructed. Then, the recombinant plasmid of pEGFP-C1-CaNBD was transformed into the mouse intestinal epithelial cells (IECs) to study the iron transportation function of CaABC. The results indicated that NBD region of CaABC gene can significantly elevate the transport efficiency of $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $HCO_3{^-}$ in IECs (P<0.05). The significance of this study is to find the ATPase inhibitors for NBD region of CaABC gene and to inhibit ATP binding and nutrient transport of CaABC transporter. Thus, C. andersoni will be killed by inhibition of nutrient uptake. This will open up a new way for treatment of cryptosporidiosis.

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1928-1934
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• 2006

The rubradirin biosynthetic gene cluster harbors 58 ORFs within a 105.6-kb sequence, which includes all of the genes responsible for the synthesis of rubradirin, as well as the primary genes relevant to regulatory, resistance, and transport functions. This gene cluster also harbors a resistance-mediating ABC transporter, RubT1, which is located at the most upstream position in the cluster. In the present study, RubT1 was expressed heterologously in E. coli, and the resistance affinity of RubT1 was determined by an antibacterial activity test, as well as by HPLC and ESI-MS analyses. Evidence clearly demonstrates that RubTl mediates rubradirin resistance as an ABC transporter.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.160.1-160.1
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• 2003

In order to confirm the biological function of ORF10 in cephabacin biosynthesis gene cluster of Lysobacter lactamgenus as an ATP-binding-cassette (ABC) transporter, the gene for ORF10 was amplified and subcloned into pET-28a(+) expression vector. After gene induction with 0.5 mM IPTG at 30~! and further cultivation at $30^~$ !. for 8 hr, a lot of the recombinant ORF10 protein was produced as soluble form in cytoplasmic fraction as well as a membrane protein in the membrane fraction as likely as other ABC transporters. (omitted)

• The Plant Pathology Journal
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• 제32권1호
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• pp.8-15
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• 2016

To identify a novel biopesticide controlling rice blast disease caused by Magnaporthe oryzae, 700 plant extracts were evaluated for their inhibitory effects on mycelial growth of M. oryzae. The L. foenum-graecum Herba extract showed the lowest inhibition concentration ($IC_{50}$) of $39.28{\mu}g/ml$, which is lower than the $IC_{50}$ of blasticidin S ($63.06{\mu}g/ml$), a conventional fungicide for rice blast disease. When treatments were combined, the $IC_{50}$ of blasticidin S was dramatically reduced to $10.67{\mu}g/ml$. Since ABC transporter genes are involved in fungicide resistance of many organisms, we performed RT-PCR to investigate the transcriptional changes of 40 ABC transporter family genes of M. oryzae treated with the plant extract, blasticidin S, and tetrandrine, a recognized ABC transporter inhibitor. Four ABC transporter genes were prominently activated by blasticidin S treatment, but were suppressed by combinational treatment of blasticidin S with the plant extract, or with tetrandrine that didn't show cellular toxicity by itself in this study. Mycelial death was detected via confocal microscopy at 24 h after plant extract treatment. Finally, subsequent rice field study revealed that the plant extract had high control efficacy of 63.3% and should be considered a biopesticide for rice blast disease. These results showed that extract of L. foenum graecum Herba suppresses M. oryzae ABC transporter genes inducing mycelial death and therefore may be a potent novel biopesticide.

• 한국응용곤충학회지
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• 제59권4호
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• pp.341-348
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• 2020

ATP-binding cassette (ABC) transporter는 다양한 기질을 세포 밖과 세포 안으로 수송하는 대표적인 수송단백질이다. 곤충에서 ABC transporter는 살충제에 대한 저항성을 발달시키는 중요한 역할을 한다. 현재까지 모델곤충인 초파리를 대상으로 ABC transporter의 살충제 교차저항성에 관한 연구는 많이 수행되어오지 않았다. 본 연구에서는 ABC transporter에 속하는 Mdr49A 유전자가 여섯 종류의 살충제에 보이는 교차저항성 기작을 형질전환 초파리를 이용하여 구명하였다. 초파리 91-R과 91-C 계통은 공통된 조상으로부터 유래되었으며 91-R은 60년 이상 DDT에 노출되었지만 91-C는 어떠한 살충제에도 노출되지 않고 유지되어 왔다. 91-R 계통의 MDR49A 단백질에서 유래된 3개의 아미노산 돌연변이를 형질전환 초파리에 과발현 시켰을 때 carbofuran에 대해서 2.0~6.7배 그리고 permethrin에 대해서 2.5~10.5배의 교차저항성을 나타낸 반면 다른 약제, abamectin, imidacloprid, methoxychlor, prothiofos에 대해서는 어떠한 교차저항성도 나타내지 않았다. 이상의 결과는 Mdr49A 유전자의 과발현과 더불어 3개의 아미노산 돌연변이는 두 개 약제, carbofuran과 permethrin에 대해 교차저항성 기능을 한다고 제시하고 있다.