Najafi Naeimeh, Hosseini Ramin, Ahmadi Ali-Reza
Women Research Centre, BioMedical Sciences Department, Alzahra University, Tehran, Iran ; Agricultural Biotechnology Department, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran.
Agricultural Biotechnology Department, Faculty of Engineering, Imam Khomeini International University, Qazvin, Iran.
Iran J Microbiol. 2013 Sep;5(3):293-8.
Astaxanthin, an orange-red carotenoid pigment, acts as a protective agent against oxidative damage to cells in vivo. The astaxanthin synthetase gene (crtS) size consists of 3995 bp. This gene has been suggested to catalyse β-carotene to astaxanthin in Phaffia rhodozyma. The aim of this research was to find any possible changes in this gene in two mutant strains, Gam1 and Gam2 (with high astaxanthin pigment production), previously created by gamma irradiation.
The astaxanthin synthetase gene sequence of Phaffia rhodozyma in the NCBI Gene bank was used to design primer. In Gam1, this gene was amplified using primers Asta F1, Asta R2, Asta F3, Asta R4. In Gam2, primers asta F1, asta R4 were used to amplify the gene. The amplified fragments were 8 sequenced using primers Asta F1, Asta R1, Asta F2, Asta R2, Asta F3, Asta R3 and Asta F4, Asta R4. Astaxanthin synthetase gene from two mutant strains, Gam1 and Gam2 were amplified using PCR. The amplified products were sequenced and aligned using the ClustalW software.
The comparison of this gene showed 98% and 99% similarities between the reference sequence and Gam1 and Gam2 mutant strains, respectively, whereas the comparison of this gene in Gam1 and Gam2 mutant strains showed 97% similarity. However, the deduced proteins showed 78% and 83% between the reference protein obtained from the wild type and Gam1 and Gam2, respectively. This similarity was 75% between the mutant strains.
虾青素是一种橙红色类胡萝卜素色素，在体内作为细胞抗氧化损伤的保护剂。虾青素合成酶基因（crtS）大小为3995 bp。该基因被认为在红发夫酵母中催化β-胡萝卜素转化为虾青素。本研究的目的是在先前通过γ射线辐照产生的两个突变菌株Gam1和Gam2（虾青素色素产量高）中寻找该基因的任何可能变化。
利用NCBI基因库中红发夫酵母的虾青素合成酶基因序列设计引物。在Gam1中，使用引物Asta F1、Asta R2、Asta F3、Asta R4扩增该基因。在Gam2中，使用引物asta F1、asta R4扩增该基因。使用引物Asta F1、Asta R1、Asta F2、Asta R2、Asta F3、Asta R3以及Asta F4、Asta R4对扩增片段进行测序。通过PCR扩增来自两个突变菌株Gam1和Gam2的虾青素合成酶基因。对扩增产物进行测序，并使用ClustalW软件进行比对。
该基因的比较显示，参考序列与Gam1和Gam2突变菌株之间的相似性分别为98%和99%，而Gam1和Gam2突变菌株中该基因的比较显示相似性为97%。然而，推导的蛋白质在从野生型获得的参考蛋白质与Gam1和Gam2之间分别显示78%和83%的相似性。突变菌株之间的这种相似性为75%。
