Gp53 protein disrupts bacterial division and biofilm formation
A single peer-reviewed laboratory study finds that the phage protein Gp53 changes gene expression in Pseudomonas aeruginosa, slowing division and reducing biofilms and movement. Restoring a division gene corrected cell shape and growth but left the other defects unresolved. The experiments distinguish regulatory pathways in bacteria; they do not establish an effective or safe treatment for human infections.
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Extra Gp53 slows growth and reduces biofilms
A protein carried by a bacteriophage, a virus that infects bacteria, disrupted growth in a laboratory strain of Pseudomonas aeruginosa. In one peer-reviewed study, overproducing Gp53 elongated cells, reduced movement and lowered biofilm formation by about threefold. Biofilms are bacterial communities attached to surfaces. The work examined bacterial physiology in the laboratory and established no clinical effect against human infection.[1]
The protein emerged from a screen of 15 possible early genes in the sewage-derived phage ΦPA1019. Gp53 consists of 126 amino acids and binds DNA, the molecule carrying genetic instructions. Researchers tested its effects in the PAO1 bacterial strain.[1]
Restoring ftsZ repairs the division defect
Gp53 bound the promoter of ftsZ, a gene involved in assembling the Z ring that divides the cell. A promoter is a DNA region controlling transcription. Fluorescence imaging showed the ring displaced from its normal central position when Gp53 was overproduced. Increasing ftsZ alongside gp53 restored growth and normal cell shape. Biofilm and movement defects persisted, separating the division pathway from those other effects.[1]
DNA-binding tests trace a wider regulatory network
Gene-expression measurements found changes in 3,342 genes: 1,642 increased and 1,700 decreased. Binding maps identified 78 sites, most within core promoter regions, including sites associated with biofilm and motility genes. After several amino-acid residues were mutated, DNA binding weakened and most affected bacterial traits recovered.[1]
Researchers relied on modelling to interpret structure after protein aggregation hampered attempts to obtain a crystal structure. The study did not test drug delivery, human safety or efficacy in a living infection model.[1]
