(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Bacteria: NE > Proteobacteria: NE > Betaproteobacteria: NE > Burkholderiales: NE > Comamonadaceae: NE > Acidovorax: NE > Acidovorax delafieldii: NE
Warning: This entry is a compilation of different species or line or strain with more than 90% amino acid identity. You can retrieve all strain data
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) Acidovorax delafieldii 2AN: N, E.
Molecular evidence
Database
No mutation 1 structure: 8C65: Crystal structure of cutinase AdCut from Acidovorax delafieldii (PBS depolymerase) No kinetic
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MHLPRSRWDIPFKEETTMTHHFSVRALLAAGALLASAAVSAQTNPYERGP APTTSSLEASRGPFSYQSFTVSRPSGYRAGTVYYPTNAGGPVGAIAIVPG FTARQSSINWWGPRLASHGFVVITIDTNSTLDQPDSRSRQQMAALSQVAT LSRTSSSPIYNKVDTSRLGVMGWSMGGGGSLISARNNPSIKAAAPQAPWS ASKNFSSLTVPTLIIACENDTIAPVNQHADTFYDSMSRNPREFLEINNGS HSCANSGNSNQALLGKKGVAWMKRFMDNDRRYTSFACSNPNSYNVSDFRV AACN
Enzyme-based depolymerization is a viable approach for recycling of poly(ethylene terephthalate) (PET). PETase from Ideonella sakaiensis (IsPETase) is capable of PET hydrolysis under mild conditions but suffers from concentration-dependent inhibition. Here, we report that this inhibition is dependent on incubation time, the solution conditions and PET surface area. Furthermore, this inhibition is evident in other mesophilic PET-degrading enzymes to varying degrees, independent of the level of PET depolymerization activity. The inhibition has no clear structural basis, but moderately thermostable IsPETase variants exhibit reduced inhibition, and the property is completely absent in the highly thermostable HotPETase, previously engineered by directed evolution, which our simulations suggest results from reduced flexibility around the active site. This work highlights a limitation in applying natural mesophilic hydrolases for PET hydrolysis, and reveals an unexpected positive outcome of engineering these enzymes for enhanced thermostability.
Title: New insights into the function and global distribution of polyethylene terephthalate (PET) degrading bacteria and enzymes in marine and terrestrial metagenomes Danso D, Schmeisser C, Chow J, Zimmermann W, Wei R, Leggewie C, Li X, Hazen T, Streit WR Ref: Applied Environmental Microbiology, 84:e2773, 2018 : PubMed
Polyethylene terephthalate (PET) is one of the most important synthetic polymers used nowadays. Unfortunately, the polymers accumulate in nature and until now, no highly active enzymes are known that can degrade it at high velocity. Enzymes involved in PET degradation are mainly alpha/beta-hydrolases like cutinases and related enzymes (E.C. 3.1.-). Currently, only a small number of such enzymes are well characterized. Within this work, a search algorithm was developed that identified 504 possible PET hydrolase candidate genes from various databases. A further global search that comprised more than 16 GB of sequence information within 108 marine and 25 terrestrial metagenomes obtained from the IMG data base detected 349 putative PET hydrolases. Heterologous expression of four such candidate enzymes verified the function of these enzymes and confirmed the usefulness of the developed search algorithm. Thereby, two novel and thermostable enzymes with high potential for downstream application were in part characterized. Clustering of 504 novel enzyme candidates based on amino acid similarities indicated that PET hydrolases mainly occur in the phylum of Actinobacteria, Proteobacteria and Bacteroidetes Within the Proteobacteria, the Beta-, Delta- and Gammaproteobacteria were the main hosts. Remarkably enough, in the marine environment, bacteria affiliated with the phylum of the Bacteroidetes appear to be the main host of PET hydrolase genes rather than Actinobacteria or Proteobacteria as observed for the terrestrial metagenomes. Our data further imply that PET hydrolases are truly rare enzymes. The highest occurrence of 1.5 hits/Mb was observed in a sample site containing crude oil.IMPORTANCE Polyethylene terephthalate (PET) accumulates in our environment without significant microbial conversion. Although few PET hydrolases are already known it is still unknown how frequent they appear and which main bacterial phyla they are affiliated with. In this study, deep sequence mining of protein databases and metagenomes demonstrated that PET hydrolases indeed are occurring at very low frequencies in the environment. Further it was possible to link them to phyla which were previously unknown to harbor such enzymes. This work contributes novel knowledge to the phylogenetic relationship, the recent evolution and the global distribution of PET hydrolases. Finally, we describe biochemical traits of four novel PET hydrolases.
A gene encoding poly(tetramethylene succinate), PBS, depolymerase, pbsA, has been cloned from Acidovorax delafieldii strain BS-3 chromosomal DNA. The clone expressed in Escherichia coli showed the ability to degrade both PBS and poly[(tetramethylene succinate)-co-adipate] that are kinds of biodegradable plastics. PBS depolymerase was considered to be a kind of lipase, since it also degrades olive oil. It had no apparent hydrophobic-amino-acid-rich region which exists in other known plastic-degrading enzymes. From the result of amino acid homology search, PbsA was found to have some similarities with lipases of Streptomyces sp. and Mollaxella sp. In the motif surrounding the active site Ser residue (Gly-X1-Ser-X2-Gly), PbsA was revealed to have a Trp residue in the X1 position instead of His which is most likely found in other bacterial lipases.
Acidovorax delafieldii poly(tetramethylene succinate) depolymerase pbs(a) depolymerase Polyesterase-lipase-cutinase PET7 AdCut
