Bt Research 2024, Vol.15, No.1, 20-29 http://microbescipublisher.com/index.php/bt 27 contribute to Bt's entomopathogenicity (Zhu et al., 2015). Second, exploring the evolutionary mechanisms and adaptive strategies of Bt through comparative genomics and phylogenomic analyses can shed light on the genetic basis of its ecological versatility and host specificity (Yuan et al., 2014; Elleuch et al., 2015). Third, developing more accurate and reliable taxonomic classification systems based on genomic data can improve the identification and characterization of Bt strains, facilitating their use in biocontrol applications (Baek et al., 2019). Finally, investigating the interactions between Bt and other organisms, including plants and fungi, can expand the potential applications of Bt as a biocontrol agent beyond insect pests (Adeniji et al., 2021). 9 Concluding Remarks The comparative genomic analysis of Bacillus thuringiensis (Bt) strains has provided significant insights into the evolutionary mechanisms and adaptive strategies of this species. Key findings include the identification of various virulence factors, fitness factors, and mobile genetic elements such as bacteriophages, IS elements, and transposases, which contribute to the genomic plasticity and adaptability of Bt strains. The study also highlighted the role of plasmids in the transfer of Cry genes, which are crucial for host specialization and adaptation to different ecological niches. Additionally, the presence of multiple virulence factors on transposable elements suggests a strategy for expanding the insecticidal spectrum and overcoming host resistance. The genomic and proteomic analyses revealed that not all annotated genes are expressed, indicating potential gene silencing or low expression levels. Furthermore, the study identified two genomovars within Bt, suggesting a need for refined taxonomic classification. Comparative genomic studies are essential for understanding the complex evolutionary processes and adaptive mechanisms in bacterial species. These studies provide a comprehensive view of the genetic diversity and functional capabilities of different strains, which is crucial for identifying key factors that contribute to pathogenicity, host specificity, and environmental adaptability. In the case of Bt, comparative genomics has elucidated the genetic basis for its ability to infect a wide range of invertebrate hosts and its potential as a biocontrol agent. Moreover, these studies facilitate the identification of novel genes and pathways that can be targeted for genetic engineering and biotechnological applications. Future research should focus on the following areas to further advance our understanding of Bt and its applications. Conduct functional studies to validate the roles of identified genes and pathways in virulence, host adaptation, and environmental survival. This includes gene knockout and overexpression experiments to determine the phenotypic effects of specific genetic elements. Investigate the molecular mechanisms underlying host-pathogen interactions, particularly the co-evolutionary dynamics between Bt and its hosts. This can be achieved through experimental evolution studies and real-time monitoring of genetic changes during host-pathogen interactions. Further refine the taxonomic classification of Bt strains using genomic and phenotypic data. This includes the identification of additional genomovars and the development of molecular markers for accurate strain identification. Explore the biocontrol potential of Bt against a broader range of pests and pathogens, including phytopathogenic fungi. This involves screening for antifungal activities and identifying the genetic basis for such activities. Leverage the genetic diversity and metabolic capabilities of Bt for biotechnological applications, such as the production of bioinsecticides, enzymes, and other valuable bioproducts. This includes optimizing fermentation processes and genetic engineering for enhanced production. By addressing these research areas, we can enhance our understanding of Bt's evolutionary mechanisms and harness its potential for various applications in agriculture, biotechnology, and medicine. Acknowledgments The publisher would like to thank Dr. Fang X. from the Hainan Institute of Tropical Agricultural Resources for reviewing and providing valuable feedback on the manuscript. Special thanks are also extended to the two anonymous peer reviewers for their review and valuable suggestions for improvements.
RkJQdWJsaXNoZXIy MjQ4ODYzNA==