sclPHA

sclPHA refers to the synthesis of polyhydroxyalkanoates (PHAs) by *Sphingomonas* species, a group of Gram-negative bacteria known for their ability to produce biodegradable polyesters. PHAs are a family of biocompatible and biodegradable thermoplastic polymers synthesized by various microorganisms under nutrient-limiting conditions, typically with an excess of carbon source. Among these, *Sphingomonas* strains have gained attention for their capacity to produce poly(3-hydroxyalkanoates) (3HAs), including poly(3-hydroxybutyrate) (P3HB) and its copolymers, which exhibit properties comparable to conventional plastics.

The process of sclPHA production involves the metabolic engineering of *Sphingomonas* strains to optimize yield and polymer properties. These bacteria naturally accumulate PHAs as intracellular carbon and energy storage compounds, but genetic modifications can enhance their productivity and expand the range of monomeric units incorporated into the polymer. For example, *Sphingomonas* species like *Sphingomonas paucimobilis* and *Sphingomonas chlorophenolicum* have been studied for their ability to produce short-chain-length (scl) PHAs, which are characterized by monomers with 3–5 carbon atoms, such as 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV).

sclPHA holds promise in bioplastic applications due to its mechanical strength, flexibility, and biodegradability in environmental settings. Research focuses on improving fermentation processes, reducing production costs, and scaling up synthesis for industrial use. Challenges include maintaining high yields, controlling polymer composition, and ensuring cost-effectiveness compared to petroleum-based plastics. Advances in metabolic engineering and synthetic biology continue to refine sclPHA production, making it a viable alternative for sustainable materials.