Structural Modeling of Luciferin 4-Monooxygenase from Human Respiratory Syncytial Virus Using Homology Techniques
Main Article Content
Abstract
Background
Human Respiratory Syncytial Virus (HRSV) is a leading etiological agent of acute lower respiratory tract infections, particularly affecting infants, elderly populations, and immunocompromised individuals, thereby imposing a substantial global health burden. Despite its clinical significance, the structural biology of several HRSV-encoded enzymes remains insufficiently characterized. Luciferin 4-Monooxygenase(L4MO)represents one such poorly understood enzyme for which no experimentally resolved three-dimensional (3D) structure is currently available.This lack of structural information limits functional interpretation and hampers structure-based antiviral drug development.
Methods
The three-dimensional structure of HRSV-derived Luciferin 4-Monooxygenase was predicted using homology modeling approaches. Amino acid sequence alignment was performed against homologous luciferin monooxygenases. Model construction was carried out using the SWISS-MODEL server. Structural validation and quality assessment were conducted using established computational tools,including PROCHECK, ERRAT, and Verify3D.
Results
The predicted L4MO model exhibited a secondary structural composition of 30.91% alpha-helices,20.55% extended strands, 7.64% beta-turns, and40.91% random coils. Model validation demonstrated high structural reliability, as reflected by an ERRAT score of 96.6% and 94.8% of residues residing within the most favored regions of the Ramachandran plot. Furthermore, the Verify3D analysis yielded a score of 83.33%, supporting the overall consistency and accuracy of the predicted structure.
Conclusion
This study presents the first validated homology-based three-dimensional structural model of Luciferin 4-Monooxygenase from HRSV.The generated model provides critical structural insights into this understudied viral enzyme and establishes a foundational framework for future investigations into its functional role in viral pathogenicity. Moreover,the predicted structure offers a valuable platform for structure-guided antiviral drug discovery targeting L4MO.
Article Details
References
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