(1. 中南大學(xué) 資源加工與生物工程學(xué)院，長(zhǎng)沙 410083；
2. 中南大學(xué) 教育部生物冶金重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083)
摘 要: 鑒定了Acidithiobacillus ferrooxidans DC (At. ferrooxidans DC)中與鋅離子轉(zhuǎn)運(yùn)相關(guān)的4個(gè)ATP-binding cassette (ABC) transporter基因，并采用Reverse Transcription quantitative real-time PCR (RT-qPCR)技術(shù)分析在不同濃度的鋅離子脅迫下這4個(gè)ATP-binding cassette (ABC) transporter基因在轉(zhuǎn)錄水平上的差異表達(dá)情況。然后利用Vector NTI、cluster X、BLAST、ORF Finder等生物信息學(xué)軟件對(duì)各基因做進(jìn)一步的生物信息學(xué)分析。結(jié)果表明：在鋅離子脅迫下，4個(gè)ABC transporter基因(AFE_2435、AFE_2436、AFE_2437、AFE_2438)的表達(dá)量均有所上調(diào)，說(shuō)明這4個(gè)基因?qū)τ阡\離子的脅迫具有很強(qiáng)的敏感性。經(jīng)生物信息學(xué)分析可知，基因AFE_2435和AFE_2436編碼位于細(xì)胞質(zhì)膜上的透性酶，AFE_2437編碼位于細(xì)胞質(zhì)膜上的ATP結(jié)合蛋白，AFE_2438編碼位于周質(zhì)空間的鋅離子結(jié)合蛋白，這4個(gè)基因共同組成了一個(gè)與鋅離子轉(zhuǎn)運(yùn)有關(guān)的ABC轉(zhuǎn)運(yùn)子。這些結(jié)果都表明這4個(gè)ABC transporter基因與DC菌中鋅離子的轉(zhuǎn)運(yùn)有著密切的關(guān)系。
關(guān)鍵字: 嗜酸氧化亞鐵硫桿菌；ABC transporter；RT-qPCR；鋅離子脅迫；生物信息學(xué)分析
（1. School of Minerals Processing and Bioengineering, Changsha 410083, China;
2. Key Laboratory of Biometallurgy, Ministry of Education, Central South University, Changsha 410083, China）
Abstract:In this study, four ATP-binding cassette (ABC) transporter genes of Acidithiobacillus ferrooxidans DC (At. ferrooxidans DC) were identified, and differential transcription of these genes during zinc ion stress were investigated by Reverse Transcription quantitative real-time PCR (RT-qPCR). And then, the genes involved in zinc ion transport were analyzed by bioinformatics software. The results show that the expressions of the four ABC transporter genes are increased differently under zinc ion stress, indicating that these genes are sensitive to zinc levels. Bioinformatics analysis shows that the proteins encode by AFE_2435, AFE_2436 are predicted to be permease proteins, whereas the protein encode by AFE_2437 is a putative ATP-bindind protein and AFE_2438 encoded a putative periplasmic cation-binding protein. The four genes together form an ABC transporter for zinc ion transport. These results strongly suggest that the four ABC transporter genes might be directly involved in zinc transport in Acidithiobacillus ferrooxidans DC.
Key words: Acidithiobacillus ferrooxidans; ABC transporter; RT-qPCR; zinc ion stress; bioinformatics analysis
