Jerdonobin and jerdofibrase are two serine proteases purified from the venom of Trimeresurus jerdonii. The Michaelis constant K(m) and the catalytic rate constant K(cat) of jerdonobin or jerdofibrase on three chromogenic substrates, H-D-Pro-Phe-Arg-pNA (S2302), H-D-Phe-pipecolyl-Arg-pNA (S2238), and H-D-Val-Leu-Lys-pNA (S2251) were obtained from lineweaver-Burk plots. Jerdofibrase could hydrolyze all three substrates, but jerdonobin had no detectable activity on S2251, suggesting a relatively broader substrate specificity for jerdofibrase than jerdonobin. By SDS-PAGE, jerdofibrase preferentially degraded Bbeta-chain of fibrinogen. It also degraded Aalpha-chain of fibrinogen with relatively slow activity, but did not act on the gamma-chain. In contrast, jerdonobin did not degrade fibrinogen within 12 h. Fibrinopeptides liberation test, identified by HPLC, showed jerdonobin released fibrinopeptide A and a small amount of fibrinopeptide B. Unlike jerdonobin, jerdofibrase mainly released fibrinopeptide B. These results indicate that the two enzymes differ in their ability to hydrolyze chromogenic substrates and in their actions on fibrinogen.
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http://dx.doi.org/10.1016/s1096-4959(02)00069-6 | DOI Listing |
Glufosinate (GLUF) and glyphosate (GLY) are nonselective phosphorus-containing amino acid herbicides that are widely used in agricultural gardens and noncultivated areas. These herbicides give rise to a number of key metabolites, with 3-methyl phosphinicopropionic acid (MPPA), -acetyl glufosinate (-acetyl GLUF), aminomethyl phosphonic acid (AMPA), -acetyl aminomethyl phosphonic acid (-acetyl AMPA), -acetyl glyphosate (-acetyl GLY), -methyl glyphosate (-methyl GLY) as the major metabolites obtained from GLUF and GLY. Extensive use of these herbicides may lead to their increased presence in the environment, especially aquatic ecosystems.
View Article and Find Full Text PDFAnal Chim Acta
February 2025
College of Food Science and Technology, Henan Key Laboratory of Cereal and Oil Food Safety Inspection and Control, Henan University of Technology, Zhengzhou, 450001, China.
Background: Aflatoxin B1 (AFB1) is a secondary metabolite produced by Aspergillus flavus and Aspergillus parasiticus. This toxin is highly carcinogenic and toxic, posing a serious threat to human and animal health. AFB1 primarily enters the human body through contaminated food, particularly peanuts, corn, nuts, and wheat.
View Article and Find Full Text PDFAnal Chim Acta
February 2025
Key Laboratory of Water Security and Water Environment Protection in Plateau Intersection (NWNU), Ministry of Education, Key Lab of Bioelectrochemistry and Environmental Analysis of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, 730070, Lanzhou, Gansu, China. Electronic address:
Background: Reliable and selective detection of dopamine is crucial for the early diagnosis of various diseases. Transition metal based-nanozymes have shown great promise in the field of colorimetric detection of dopamine due to their remarkable stability and exceptional catalytic efficiency. However, these transition metal-based nanozymes typically function through a chromogenic reaction that relies on additional organic substrates, such as 3,3',5,5'-tetramethylbenzidine, to generate a detectable signal.
View Article and Find Full Text PDFBiotechnol Bioeng
January 2025
Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, St. Paul, Minnesota, USA.
N-acyl l-homoserine lactones are signaling molecules used by numerous bacteria in quorum sensing. Some bacteria encode lactonases, which can inactivate these signals. Lactonases were reported to inhibit quorum sensing-dependent phenotypes, including virulence and biofilm.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Institute of Food Chemistry, Department of Food Chemistry and Analytical Chemistry, University of Hohenheim, Garbenstraße 28, 70599 Stuttgart, Germany. Electronic address:
As an established analytical method, high-performance thin-layer chromatography (HPTLC) offers powerful capabilities. This study focused on its application to analyze chlorinated paraffins (CP) by planar solid phase extraction (pSPE). Based on previous work, an irradiation chamber was developed to investigate the derivatization process on planar thin-layers and ensure a robust and reproducible analysis.
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