Dataset Information

Estimating Nanoscale Surface Roughness of Polyethylene Terephthalate Fibers.

ABSTRACT: Quantitation of surface roughness is difficult, if subtle, but significant differences cause an uncommon variance. We used atomic force microscopy to measure the surface roughness of polyethylene terephthalate (PET) fibers before and after a 30 s plasma treatment of 300 W. Samples were measured multiple times at different locations, in four scan sizes. The surface roughness was expressed in terms of nine roughness parameters. Despite the large number of data, simple statistics was not able to detect significant differences in roughness before and after plasma treatment. A factorial analysis of variance (ANOVA) of the normalized data and a sum of ranking differences analysis using four types of data preprocessing and their factorial ANOVA confirmed that (i) the plasma treatment had roughened the PET fiber surface; (ii) the roughness increases with the scanned area in the measured range; and (iii) what the best roughness parameters are in discriminating between surfaces before and after treatment. Although the compared roughness estimators were on different scales, a roughness estimation of the nanoscale surfaces was feasible, where other methods fail. The presented methodology can be applied widely and unambiguously for highly different method comparison tasks.

SUBMITTER: Romanszki L

PROVIDER: S-EPMC7045555 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Estimating Nanoscale Surface Roughness of Polyethylene Terephthalate Fibers.

Románszki Loránd L Klébert Szilvia S Héberger Károly K

ACS omega 20200213 7

Quantitation of surface roughness is difficult, if subtle, but significant differences cause an uncommon variance. We used atomic force microscopy to measure the surface roughness of polyethylene terephthalate (PET) fibers before and after a 30 s plasma treatment of 300 W. Samples were measured multiple times at different locations, in four scan sizes. The surface roughness was expressed in terms of nine roughness parameters. Despite the large number of data, simple statistics was not able to de ...[more]

PMID: 32118182

Similar Datasets

Project description:Biodegradation of terephthalate (TPA) is a highly desired catabolic process for the bacterial utilization of this polyethylene terephthalate (PET) depolymerization product, but to date, the structure of terephthalate dioxygenase (TPDO), a Rieske oxygenase (RO) that catalyzes the dihydroxylation of TPA to a cis-diol, is unavailable. In this study, we characterized the steady-state kinetics and first crystal structure of TPDO from Comamonas testosteroni KF1 (TPDOKF1). TPDOKF1 exhibited substrate specificity for TPA (kcat/Km = 57 ± 9 mM-1 s-1). The TPDOKF1 structure harbors characteristic RO features as well as a unique catalytic domain that rationalizes the enzyme's function. The docking and mutagenesis studies reveal that its substrate specificity for TPA is mediated by the Arg309 and Arg390 residues, positioned on opposite faces of the active site. Additionally, residue Gln300 is also proven to be crucial for the activity, as its mutation to alanine decreases the activity (kcat) by 80%. This study delineates the structural features that dictate the substrate recognition and specificity of TPDO. IMPORTANCE Global plastic pollution has become the most pressing environmental issue. Recent studies on enzymes depolymerizing polyethylene terephthalate plastic into terephthalate (TPA) show some potential for tackling this. Microbial utilization of this released product, TPA, is an emerging and promising strategy for waste-to-value creation. Research in the last decade has identified terephthalate dioxygenase (TPDO) as being responsible for initiating the enzymatic degradation of TPA in a few Gram-negative and Gram-positive bacteria. Here, we determined the crystal structure of TPDO from Comamonas testosteroni KF1 and revealed that it possesses a unique catalytic domain featuring two basic residues in the active site to recognize TPA. Biochemical and mutagenesis studies demonstrated the crucial residues responsible for the substrate specificity of this enzyme.

Dataset Information

Estimating Nanoscale Surface Roughness of Polyethylene Terephthalate Fibers.

Publications

Estimating Nanoscale Surface Roughness of Polyethylene Terephthalate Fibers.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets