2 research outputs found
Hydrolysis of Ionic Phthalic Acid Based Polyesters by Wastewater Microorganisms and Their Enzymes
Water-soluble
polyesters are used in a range of applications today
and enter wastewater treatment plants after product utilization. However,
little is known about extracellular enzymes and aquatic microorganisms
involved in polyester biodegradation and mineralization. In this study,
structurally different ionic phthalic acid based polyesters (the number-average
molecular weights (<i>M</i><sub>n</sub>) 1770 to 10 000
g/mol and semi crystalline with crystallinity below 1%) were synthesized
in various combinations. Typical wastewater microorganisms like <i>Pseudomonas</i> sp. were chosen for <i>in-silico</i> screening toward polyester hydrolyzing enzymes. Based on the <i>in-silico</i> search, a cutinase from <i>Pseudomonas pseudoalcaligenes</i> (PpCutA) and a putative lipase from <i>Pseudomonas pelagia</i> (PpelaLip) were identified. The enzymes PpCutA and PpelaLip were
demonstrated to hydrolyze all structurally different polyesters. Activities
on all the polyesters were also confirmed with the strains <i>P. pseudoalcaligenes</i> and <i>P. pelagia</i>. Parameters
identified to enhance hydrolysis included increased water solubility
and polyester hydrophilicity as well as shorter diol chain lengths.
For example, polyesters containing 1,2-ethanediol were hydrolyzed
faster than polyesters containing 1,8-octanediol. Interestingly, the
same trend was observed in biodegradation experiments. This information
is important to gain a better mechanistic understanding of biodegradation
processes of polyesters in WWTPs where the extracellular enzymatic
hydrolysis seems to be the limiting step
Hydrolysis of Ionic Phthalic Acid Based Polyesters by Wastewater Microorganisms and Their Enzymes
Water-soluble
polyesters are used in a range of applications today
and enter wastewater treatment plants after product utilization. However,
little is known about extracellular enzymes and aquatic microorganisms
involved in polyester biodegradation and mineralization. In this study,
structurally different ionic phthalic acid based polyesters (the number-average
molecular weights (<i>M</i><sub>n</sub>) 1770 to 10 000
g/mol and semi crystalline with crystallinity below 1%) were synthesized
in various combinations. Typical wastewater microorganisms like <i>Pseudomonas</i> sp. were chosen for <i>in-silico</i> screening toward polyester hydrolyzing enzymes. Based on the <i>in-silico</i> search, a cutinase from <i>Pseudomonas pseudoalcaligenes</i> (PpCutA) and a putative lipase from <i>Pseudomonas pelagia</i> (PpelaLip) were identified. The enzymes PpCutA and PpelaLip were
demonstrated to hydrolyze all structurally different polyesters. Activities
on all the polyesters were also confirmed with the strains <i>P. pseudoalcaligenes</i> and <i>P. pelagia</i>. Parameters
identified to enhance hydrolysis included increased water solubility
and polyester hydrophilicity as well as shorter diol chain lengths.
For example, polyesters containing 1,2-ethanediol were hydrolyzed
faster than polyesters containing 1,8-octanediol. Interestingly, the
same trend was observed in biodegradation experiments. This information
is important to gain a better mechanistic understanding of biodegradation
processes of polyesters in WWTPs where the extracellular enzymatic
hydrolysis seems to be the limiting step