Ahmed, S. F., Quadeer, A. A., & McKay, M. R. (2020). Preliminary Identification of Potential Vaccine Targets for the COVID-19 Coronavirus (SARS-CoV-2) Based on SARS-CoV Immunological Studies. Viruses, 12(3), 254.
Preliminary Identification of Potential Vaccine Targets for the COVID-19 Coronavirus (SARS-CoV-2) Based on SARS-CoV Immunological Studies
3. Results
3.1. Structural Proteins of SARS-CoV-2 Are Genetically Similar to SARS-CoV, but Not to MERS-CoV
SARS-CoV-2 has been observed to be close to SARS-CoV—much more so than MERS-CoV—based on full-length genome phylogenetic analysis [9,12]. We checked whether this is also true at the level of the individual structural proteins (S, E, M, and N). A straightforward reference-sequence-based comparison indeed confirmed this, showing that the
M, N, and E proteins of SARS-CoV-2 and SARS-CoV have over 90% genetic similarity, while that of the S protein was notably reduced (but still high) (Figure 1a). The similarity between SARS-CoV-2 and MERS-CoV, on the other hand, was substantially lower for all proteins (Figure 1a); a feature that was also evident from the corresponding phylogenetic trees (Figure 1b). We note that while the former analysis (Figure 1a) was based on the reference sequence of each coronavirus, it is indeed a good representative of the virus population, since few amino acid mutations have been observed in the corresponding sequence data (Figure S1). It is also noteworthy that while MERS-CoV is the more recent coronavirus to have infected humans, and is comparatively more recurrent (causing outbreaks in 2012, 2015, and 2018 ), SARS-CoV-2 is closer to SARS-CoV, which has not been observed since 2004.
ایک وائرس پہلے آ چکے سارس وائرس سے لگ بھگ پوری مشابہت رکھتا ہے۔ قدرتی ماحول میں وائرسز میں اس حد تک میوٹیشنز آنا معمول کی بات ہے۔ وائرس انسانوں میں پھیلتا بھی اسی خطے میں ہے جہاں سارس کی ابتداء ہوئی تھی۔ قدرتی طور پر ایک ایسے واقعے کا ہونا اچھی طرح سمجھ آتا ہے۔ اس پر اصرار کرنا کہ یہ ایک قدرتی واقعہ ہو ہی نہیں سکتا اور لازمی اس کے پیچھے کوئی "خفیہ ہاتھ" ہے، وہی بات ہے کہ یا تو ہم بڑے جینیس ہیں کہ ریسرچ سے واقفیت پیدا کیے بغیر ہی بیٹھے بیٹھے ایک عظیم سازش کو بے نقاب کر دیا یا پھر اس کی حیثیت بونگیوں کے سوا کچھ نہیں ہے۔
سارس کوروناوائرس کے متعلق مزید
Lau, S. K. P., Li, K. S. M., Huang, Y., Shek, C.-T., Tse, H., Wang, M., … Yuen, K.-Y. (2010). Ecoepidemiology and Complete Genome Comparison of Different Strains of Severe Acute Respiratory Syndrome-Related Rhinolophus Bat Coronavirus in China Reveal Bats as a Reservoir for Acute, Self-Limiting Infection That Allows Recombination Events. Journal of Virology, 84(6), 2808–2819.
https://doi.org/10.1128/jvi.02219-09
The present study revealed that recombination events are common between different SARSr-Rh-BatCoV strains from different species of bats and geographical locations, which may account for the emergence of a civet SARSr-CoV capable of cross-species transmission from bats to civets and from civets to humans.
