phaZ1

phaZ1 is a gene encoding a polyhydroxyalkanoate (PHA) depolymerase in bacteria. It designates one member of a family of enzymes that mobilize stored PHA granules by breaking down the polymer into monomeric hydroxyalkanoates, which the cell can reuse as carbon and energy sources. The exact name and number of phaZ variants can vary between species, so phaZ1 refers to a specific depolymerase isoform in a given organism.

Functionally, PhaZ1 enzymes catalyze the hydrolysis of PHA polymers that accumulate intracellularly as granules. This depolymerization typically occurs when cells experience nutrient limitation or other stresses, allowing the release of monomers for metabolism. PhaZ1 enzymes are often part of the broader PHA metabolism network and may exhibit substrate preferences for different PHA types, with activity that can be influenced by environmental conditions such as pH, temperature, and ionic strength. In many bacteria, depolymerases are associated with the cell envelope and can be secreted to the periplasm or extracellular space, facilitating access to granules.

Genomic context and regulation can vary by species. phaZ1 may be located within a locus containing other PHA-related genes, such as those encoding the PHA biosynthesis pathway, and its expression is commonly coordinated with cellular carbon and energy needs. Regulatory elements may respond to carbon source availability and growth phase, and genetic studies often examine the effects of phaZ1 disruption on PHA turnover.

Applications and research focus include understanding PHA metabolism, improving bioplastic recycling, and exploring depolymerase enzymes for biotechnological uses. See also polyhydroxyalkanoates, phaZ, and PHA metabolism.