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Published on: June 4, 2016
Structural and functional insights into Mimivirus ORFans.
Harpreet Kaur Saini1, Daniel Fischer
1Computer Science and Engineering Dept., University at Buffalo, Buffalo, NY 14260-2000, USA. hksaini@cse.buffalo.edu <hksaini@cse.buffalo.edu>
BMC Genomics
|May 11, 2007
Summary
Researchers used computational methods to predict the 3D structures and functions of Mimivirus ORFans. Six unannotated ORFans were functionally classified, advancing our understanding of this giant virus.
Area of Science:
- Virology
- Structural Biology
- Bioinformatics
Background:
- Mimivirus, a giant virus, possesses unique genes with eukaryotic homology, yet many encoded proteins remain functionally uncharacterized.
- A significant portion of Mimivirus proteins, termed ORFans, lack sequence similarity to known proteins, hindering functional annotation via standard methods.
Purpose of the Study:
- To computationally characterize Mimivirus ORFans by predicting their 3D structures and inferring functions.
- To identify potential functional sites within these ORFans for future experimental validation.
Main Methods:
- Application of fold-recognition methods to predict 3D structures of Mimivirus ORFans.
- Analysis of conserved functional motifs within predicted structures and sequence-template alignments to infer function.
Main Results:
- High-confidence 3D structural assignments were obtained for 21 Mimivirus ORFans.
- Functional predictions were successfully derived for 6 ORFans, classifying them into specific protein families including esterases, deacetylases, kinases, DNA glycosylases, BTB domains, and translation initiation factors.
Conclusions:
- Stringent fold-recognition criteria enabled the assignment of 3D structures to 21 Mimivirus ORFans.
- Functional attributes were successfully assigned to 6 ORFans based on structural models and motif conservation analysis.
- These computational findings provide a basis for experimental verification and further studies on remaining Mimivirus ORFans.
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