Genomic and structural insights into the high-efficiency poly(3-hydroxybutyrate) biodegradation in Terrabacter sp....

Area of Science:

• Microbiology
• Biochemistry
• Environmental Science

Background:

• Poly(3-hydroxybutyrate) (PHB) is a biodegradable bioplastic with potential applications in sustainable materials.
• Efficient biodegradation of PHB is crucial for effective bioplastic waste management.
• Identifying microbial strains with high PHB degradation capabilities is an active area of research.

Purpose of the Study:

• To investigate the biodegradation efficiency of the freshwater isolate Terrabacter sp. AAH1 on PHB.
• To elucidate the genomic and molecular mechanisms underlying PHB biodegradation by Terrabacter sp. AAH1.
• To assess the potential of Terrabacter sp. AAH1 as a biocatalyst for bioplastic waste management.

Main Methods:

• Polymer biodegradation assays measuring weight loss.
• Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) for surface and chemical analysis.
• Comparative genomic analysis and in silico structural modeling of putative depolymerase enzymes.

Main Results:

• Terrabacter sp. AAH1 achieved 98.02 ± 0.08% PHB weight loss within 12 days, indicating highly efficient biodegradation.
• SEM and FTIR confirmed extensive surface erosion and hydrolytic cleavage of ester bonds during degradation.
• Genomic analysis identified a unique metabolic pathway involving a secreted putative PHB depolymerase (Te_EPD) and intracellular enzymes for PHB breakdown.

Conclusions:

• Terrabacter sp. AAH1 possesses a specialized genomic architecture enabling efficient PHB biodegradation.
• The identified putative depolymerase Te_EPD shows potential for extracellular PHB hydrolysis.
• This strain represents a promising candidate biocatalyst for bioplastic waste management applications.