Functional Annotation of Gordonia Phage Minor Tail Proteins Using AlphaFold and Structural Homology Searches

Functional Annotation of Gordonia Phage Minor Tail Proteins Using AlphaFold and Structural Homology Searches

Alvin Sherman Library

Bacteriophages are viruses that infect bacteria. The basic phage structure consists of a DNA or RNA genome encased in a capsid protein shell. Some may also have a tail, important for attachment and genome delivery into the bacterial host. Recently, the structure of mycobacteriophage Bxb1 was characterized and determined to have 10 minor tail proteins, each assigned a unique function. The genomes of Gordonia rubripertincta phages Fribs8, Genamy16, Alyssamiracle, and NovaSharks were annotated, depicting several minor tai proteins. However, the specific functions were not determined. Therefore, the goal of this research was to assign a specific function to the minor tail proteins of Gordonia phages by evaluating their structural homology to the Bxb1 phage. The phage genome maps were reviewed on Phamerator to determine the number of minor tail proteins and amino acid sequences. HHpred was used to determine if they aligned with Bxb1 proteins. Preliminary results identified similarity of the Gordonia phage minor tail proteins to the Bxb1 tail tip cage, tail spike, baseplate hub, tail collar fiber, and tail wing brush. Then, the structures of the proteins were determined using AlphaFold. ChimeraX was then used to align the structural similarity. Additional Gordonia phage minor tail proteins are being evaluated. These findings contribute to a better understanding of Gordonia phage virion structure, which could be useful in the future for the development of phage therapy.