Secreted phospholipase A2s (sPLA2s) participate in physiological function by their enzyme and receptor binding activity. Muscle-type phospholipase A2 receptor (M-type PLA2R) is the sPLA2 binding protein with the highest affinity so far, and also inhibits the enzyme activity of sPLA2. There is species specificity and pH dependence for the binding of M-type PLA2R to sPLA2.
View Article and Find Full Text PDFCholestatic liver disease (CLD) is a severe disease, which can progress to liver cirrhosis, even liver cancer. Hepatic stellate cells (HSCs) activation plays a crucial role in CLD development. Bone mesenchymal stem cells (BMSCs) treatment was demonstrated to be beneficial in liver diseases.
View Article and Find Full Text PDFPrep Biochem Biotechnol
February 2024
Secreted phospholipase A2s (sPLA2s) are a group of enzymes with 6-8 disulfide bonds that participate in numerous physiological processes by catalyzing the hydrolysis of phospholipids at the sn-2 position. Due to their high content of disulfide bonds and hydrolytic activity toward cell membranes, obtaining the protein of sPLA2s in the soluble and active form is challenging, which hampers their functional study. In this study, one member of recombinant human sPLA2s, tag-free group IIE (GIIE), was expressed in The protein GIIE was purified from the crude culture supernatant by a two-step chromatography procedure, a combination of cation exchange and size-exclusion chromatography.
View Article and Find Full Text PDFBackground: Symptomatic urachal anomalies are rare disorders. The management of urachal remnants has historically been surgical excision because of the connection between urachal remnants and risk of malignancy development later in life. However, recent literature suggests that urachal anomalies that do not extend to the bladder can be treated with conservative management.
View Article and Find Full Text PDFSheng Wu Gong Cheng Xue Bao
July 2021
Human secreted phospholipase A2 GIIE (hGIIE) is involved in inflammation and lipid metabolism due to its ability of hydrolyzing phospholipids. To reveal the mechanism of substrate head-group selectivity, we analyzed the effect of mutation of hGIIE on its activity and selectivity. hGIIE structural analysis showed that E54 might be related to its substrate head-group selectivity.
View Article and Find Full Text PDFBiochem Biophys Res Commun
June 2021
Secreted phospholipase A2s (sPLA2s) are calcium dependent enzymes involved in various biological events such as lipid metabolism and inflammation. We previously identified the second calcium (Ca2) binding site of human sPLA2 Group IIE (hGIIE) by structural study and suggested that Asn21 act as the switch of Ca2 binding to modulate the enzymatic activity, but the detailed Ca2 binding mechanism is still unclear. Combined with enzymatic assay, model analysis and calcium binding affinity data for mutated hGIIE proteins, we herein further demonstrate that the flexibly bound Ca2 is essential for the catalysis of hGIIE, unlike the stable binding of Ca2 in hGIIA that replenishes the calcium in the typical loop during the reaction.
View Article and Find Full Text PDFSecreted phospholipases A2 (sPLA2) group IIE (GIIE) is involved in several biological events, such as lipid metabolism and possibly inflammation that may mainly depend on its catalytic reaction. We previously showed that Asn21 is a critical residue that contributes to the enzymatic activity of hGIIE, but the underlying mechanism is still not clear. Here, combined with crystal structures and mutagenesis studies of the Asn21Gly mutant, we demonstrate that Asn21 acts as a switch responsible for the calcium binding and the catalytic efficiency.
View Article and Find Full Text PDFSecreted phospholipases As (sPLAs) are involved in various pathological conditions such as rheumatoid arthritis and cardiovascular disease. Many inhibitors were developed and studied in clinical trials, but none have reached the market yet. This failure may be attributed to the lack of subtype selectivity for these inhibitors.
View Article and Find Full Text PDFUnlabelled: MAS1 from marine Streptomyces sp. strain W007 belongs to the bacterial lipase I.7 subfamily and is characterized as a thermostable and nonregiospecific lipase.
View Article and Find Full Text PDFOne approach to treating the dengue virus infection is to inhibit its NS2B-NS3 protease that plays a vital role in virus maturation. However, the lack of structural information on the active conformation of the protease hindered related drug design. With a co-expression system, we obtained the active two-component protease in its unlinked form.
View Article and Find Full Text PDFMost lipases contain a lid domain to shield the hydrophobic binding site from the water environment. The lid, mostly in helical form, can undergo a conformational change to expose the active cleft during the interfacial activation. Here we report the crystal structures of Malassezia globosa LIP1 (SMG1) at 1.
View Article and Find Full Text PDFLipases from microorganisms have multi-faceted properties and play an important role in ever-growing modern biotechnology and, consequently, it is of great significance to develop new ones. In the present work, a lipase gene from Candida albicans (CaLIP10) was cloned and two non-unusual CUG serine codons were mutated into universal codons, and its expression in Pichia pastoris performed optimally, as shown by response surface methodology. Optimal conditions were: initial pH of culture 6.
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