Influence of ammonium salts on the lipase/esterase activity assay using <i>p</i>‐nitrophenyl esters as substrates

Yan, Hong De; Zhang, Yin Jun; Liu, Hong Cai; Zheng, Jian; Zhao, Wang

doi:10.1002/bab.1095

Cited by 12 publications

(4 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Subsequently, it was observed that ammonium ions could trigger the hydrolysis of the substrate used in the assay, leading to false-positive results. The same observation was published for different p NP-esters . Further, it was observed that when ammonium sulphate was removed by dialysis, the volumetric activity of the supernatant was reduced to the initial value.…”

Section: Resultssupporting

confidence: 79%

“…The same observation was published for different pNP-esters. 29 Further, it was observed that when ammonium sulphate was removed by dialysis, the volumetric activity of the supernatant was reduced to the initial value. The obtained results indicate that lipase has not been precipitated at these conditions (70% ammonium sulphate, T = 4 °C, t = 5 h, pH 8, 1.89 mg cm −3 proteins).…”

Section: ■ Results and Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Sustainable Production of Lipase from Thermomyces lanuginosus: Process Optimization and Enzyme Characterization

Šibalić

Šalić

Tušek

et al. 2020

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The lipase production process by Thermomyces lanuginosus solid-state cultivation on hull-less pumpkin oil pomace was studied. A reduced quadratic model of lipase production was proposed based on the optimization of five independent variables followed by a model validation with 95% accuracy. Maximum lipase production was obtained after a process duration of 2 days with high volumetric and specific activity. The enzyme activity of 391 U g db −1 proves that the developed process is highly efficient. Partial purification of the crude enzymatic extracts was investigated, and a highly concentrated lipase liquid preparation with a volumetric activity of 422 U cm −3 was achieved. The sustainability of the process was confirmed by a snapshot assessment using the green chemistry matrix of the E-factor and the process mass intensity, quoting on the mass efficiency. The new lipase process was in the range of the best white biotechnology processes, as per green chemistry metrics ranking.

show abstract

Section: Resultssupporting

confidence: 79%

Section: ■ Results and Discussionmentioning

confidence: 99%

Sustainable Production of Lipase from Thermomyces lanuginosus: Process Optimization and Enzyme Characterization

Šibalić

Šalić

Tušek

et al. 2020

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…Esterase and lipase activities were quantified by following the hydrolysis of p-nitrophenyl esters and measured spectrophotometrically at 415 nm (De Yan et al, 2013). Substrate p-NPB for esterase activity and substrate 4-p-NPC for lipase activity were prepared as follows.…”

Section: Lipolytic Activity Quantificationmentioning

confidence: 99%

The secretome of the fish pathogen Tenacibaculum maritimum includes soluble virulence-related proteins and outer membrane vesicles

Escribano

Balado

Toranzo

et al. 2023

Front. Cell. Infect. Microbiol.

View full text Add to dashboard Cite

Tenacibaculum maritimum, the etiological agent of tenacibaculosis in marine fish, constitutively secretes extracellular products (ECPs) in which protein content has not been yet comprehensively studied. In this work, the prevalence of extracellular proteolytic and lipolytic activities related to virulence was analyzed in 64 T. maritimum strains belonging to the O1–O4 serotypes. The results showed the existence of a great intra-specific heterogeneity in the enzymatic capacity, particularly within serotype O4. Thus, the secretome of a strain belonging to this serotype was characterized by analyzing the protein content of ECPs and the possible production of outer membrane vesicles (OMVs). Notably, the ECPs of T. maritimum SP9.1 contain a large amount of OMVs that were characterized by electron microscopy and purified. Thus, ECPs were divided into soluble (S-ECPs) and insoluble fractions (OMVs), and their protein content was analyzed by a high-throughput proteomic approach. A total of 641 proteins were identified in ECPs including some virulence-related factors, which were mainly found in one of the fractions, either OMVs or S-ECPs. Outer membrane proteins such as TonB-dependent siderophore transporters and the type IX secretion system (T9SS)-related proteins PorP, PorT, and SprA appeared to be mainly associated with OMVs. By contrast, putative virulence factors such as sialidase SiaA, chondroitinase CslA, sphingomyelinase Sph, ceramidase Cer, and collagenase Col were found only in the S-ECPs. These findings clearly demonstrate that T. maritimum releases, through surface blebbing, OMVs specifically enriched in TonB-dependent transporters and T9SS proteins. Interestingly, in vitro and in vivo assays also showed that OMVs could play a key role in virulence by promoting surface adhesion and biofilm formation and maximizing the cytotoxic effects of the ECPs. The characterization of T. maritimum secretome provides insights into ECP function and can constitute the basis for future studies aimed to elucidate the full role of OMVs in the pathogenesis of fish tenacibaculosis.

show abstract

“…Esterase activity was determined spectrophotometrically using 4-nitrophenyl butyrate as a specific esterase substrate hydrolyzed to a colored product 4nitrophenolate ion with an optical absorbance λ max = 400 nm. 31 The assay was performed at different bulk pH values to analyze the esterase activity dependence on the pH. The used pH values were based on the known dependence of the esterase activity on solution pH.…”

Section: Methodsmentioning

confidence: 99%

Switchable Biocatalytic Reactions Controlled by Interfacial pH Changes Produced by Orthogonal Biocatalytic Processes

Wells

Smutok

Melman

et al. 2021

ACS Appl. Mater. Interfaces

View full text Add to dashboard Cite

Enzymes immobilized on a nano-structured surface were used to switch the activity of one enzyme by a local pH change produced by another enzyme. Immobilized amyloglucosidase (AMG) and trypsin were studied as examples of the pH-dependent switchable “target enzymes.” The reactions catalyzed by co-immobilized urease or esterase were increasing or decreasing the local pH, respectively, thus operating as “actuator enzymes.” Both kinds of the enzymes, producing local pH changes and changing biocatalytic activity with the pH variation, were orthogonal in terms of the biocatalytic reactions; however, their operation was coupled with the local pH produced near the surface with the immobilized enzymes. The “target enzymes” (AMG and trypsin) were changed reversibly between the active and inactive states by applying input signals (urea or ester, substrates for the urease or esterase operating as the “actuator enzymes”) and washing them out with a new portion of the background solution. The developed approach can potentially lead to switchable operation of several enzymes, while some of them are inhibited when the others are activated upon receiving external signals processed by the “actuator enzymes.” More complex systems with branched biocatalytic cascades can be controlled by orthogonal biocatalytic reactions activating selected pathways and changing the final output.

show abstract

Influence of ammonium salts on the lipase/esterase activity assay using p‐nitrophenyl esters as substrates

Cited by 12 publications

References 19 publications

Sustainable Production of Lipase from Thermomyces lanuginosus: Process Optimization and Enzyme Characterization

Sustainable Production of Lipase from Thermomyces lanuginosus: Process Optimization and Enzyme Characterization

The secretome of the fish pathogen Tenacibaculum maritimum includes soluble virulence-related proteins and outer membrane vesicles

Switchable Biocatalytic Reactions Controlled by Interfacial pH Changes Produced by Orthogonal Biocatalytic Processes

Contact Info

Product

Resources

About