Bovine annexin V isoforms: A molecular weight difference of 4 kD by SDS-PAGE, 9 D by mass spectrometry

Abstract Background The accurate identification of carbapenem resistance mechanisms is decisive for the appropriate selection of antibiotic regimens. Numerous methods can detect carbapenemase-producing carbapenem-resistant bacteria (CPCR). However, non-CPCR (NCPCR) are routinely assumed to display porin loss as a diagnosis of exclusion. No further confirmatory tests are performed since the gold standard (sodium dodecylsulfate polyacrylamide gel electrophoresis, SDS–PAGE) is laborious and time consuming. We propose a test for rapid and easy detection of porin loss by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Methods Clinical meropenem-resistant Enterobacterales strains (10 CPCR, 10 NCPCR) and control strains recommended by EUCAST (5 carbapenemase-producing, one with porin loss, one-negative control) were analyzed. Membrane proteins were extracted by successive centrifugation of bacterial suspensions (McFarland 0.5) and addition of ethanol, formic acid and acetonitrile. MALDI-TOF MS of the protein extracts was performed on a 96-spot target (Bruker Daltonics, Germany). Peaks between 35 and 40 kDa were analyzed for the presence of porins and compared with the bands observed in the SDS–PAGE of the protein extracts. Results Within the molecular weight range of 35–40 kDa, the MALDI-TOF MS-based method revealed peaks in all CPCR isolates corresponding to those observed in the carbapenemase-producing control strains. In contrast, the control strain with porin loss as well as all CNCR isolates showed a lower quantity of peaks in this range. All peaks observed correlated with the bands observed in the SDS–PAGE of the protein extracts at the corresponding molecular weight (Figure 1). Conclusion Yielding results that reliably correspond to the current gold standard, we propose a method for accelerated detection of porin loss as an alternative to the diagnosis of exclusion usually made in routine settings. With a processing time of approximately 20 minutes, the method can be easily implemented in the clinical setting. Applying this MALDI-TOF MS-based approach, valuable information will be provided about a resistance mechanism that otherwise remains unexplained. Disclosures All authors: No reported disclosures.

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Deep proteomic profiling of vasopressin-sensitive collecting duct cells. I. Virtual Western blots and molecular weight distributions

AJP Cell Physiology ◽

10.1152/ajpcell.00213.2015 ◽

2015 ◽

Vol 309 (12) ◽

pp. C785-C798 ◽

Cited By ~ 16

Author(s):

Chin-Rang Yang ◽

Pumipat Tongyoo ◽

Milad Emamian ◽

Pablo C. Sandoval ◽

Viswanathan Raghuram ◽

...

Keyword(s):

Mass Spectrometry ◽

Molecular Weight ◽

Cell Line ◽

Collecting Duct ◽

Mass Spectrometry Data ◽

Epithelial Cell Line ◽

Proteomic Profiling ◽

Western Blots ◽

Sds Page ◽

Public Data

The mouse mpkCCD cell line is a continuous cultured epithelial cell line with characteristics of renal collecting duct principal cells. This line is widely used to study epithelial transport and its regulation. To provide a data resource useful for experimental design and interpretation in studies using mpkCCD cells, we have carried out “deep” proteomic profiling of these cells using three levels of fractionation (differential centrifugation, SDS-PAGE, and HPLC) followed by tandem mass spectrometry to identify and quantify proteins. The analysis of all resulting samples generated 34.6 gigabytes of spectral data. As a result, we identified 6,766 proteins in mpkCCD cells at a high level of stringency. These proteins are expressed over eight orders of magnitude of protein abundance. The data are provided to users as a public data base ( https://helixweb.nih.gov/ESBL/Database/mpkFractions/ ). The mass spectrometry data were mapped back to their gel slices to generate “virtual Western blots” for each protein. For most of the 6,766 proteins, the apparent molecular weight from SDS-PAGE agreed closely with the calculated molecular weight. However, a substantial fraction (>15%) of proteins was found to run aberrantly, with much higher or much lower mobilities than predicted. These proteins were analyzed to identify mechanisms responsible for altered mobility on SDS-PAGE, including high or low isoelectric point, high or low hydrophobicity, physiological cleavage, residence in the lysosome, posttranslational modifications, and expression of alternative isoforms due to alternative exon usage. Additionally, this analysis identified a previously unrecognized isoform of aquaporin-2 with apparent molecular mass <20 kDa.

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Effects of colloidal TiO2 particles on photodegradation of dissolved organic matter from different sources: Based on molecular weight difference analysis

Journal of Lake Sciences ◽

10.18307/2021.0417 ◽

2021 ◽

Vol 33 (4) ◽

pp. 1163-1174

Author(s):

Li Fangfang ◽

◽

Xu Huacheng ◽

Jiang Helong

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Dissolved Organic Matter ◽

Difference Analysis ◽

Weight Difference ◽

Molecular Weight Difference ◽

Different Sources

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Extraction, Isolation and Identification of Antimicrobial Substances from Bacillus amyloliquefaciens CMN1308

Notulae Botanicae Horti Agrobotanici Cluj-Napoca ◽

10.15835/nbha45110654 ◽

2017 ◽

Vol 45 (1) ◽

pp. 308-315

Author(s):

Yingyou FANG ◽

Linling LI ◽

Yongliang ZHENG ◽

Honghui YUAN ◽

Xuehua ZHANG ◽

...

Keyword(s):

Mass Spectrometry ◽

Molecular Weight ◽

Bacillus Amyloliquefaciens ◽

Protein Characterization ◽

Mass Spectrometry Analysis ◽

Antimicrobial Protein ◽

Isolation And Identification ◽

Spectrometry Analysis ◽

Antimicrobial Substances ◽

Sds Page

Four separation methods of antimicrobial substances produced by CMN1308 (Bacillus amyloliquefaciens) were evaluated and selected according to number of antimicrobial substances and its activity in vitro. The results showed that extraction by acid precipitation of the fermentation supernatant of CMN1308 was the best with a diameter of inhibition zone of pathogen fungi P. expansum of 12.3 mm in a laboratory bioassay. Applying a silica thin layer chromatography (TLC), SDS-PAGE and other separation technologies we isolate antimicrobial substances, and the separated band were cut off for mass spectrometry analysis. The TLC of crude extract of CMN1308 show a topical band corresponding with the surfactin standard (Rf value =0.75), proved that the strain CMN1308 can produce this surface active compound. The mycoprotein extracted from CMN1308 was separated by Tricine-SDS-PAGE modified with the addition of urea in the separation gel. After mass spectrometric analysis and protein characterization, the isolated mycoprotein showed a maximum ion peak at M/Z of 2679 and molecular weight of 29.5 kDa, matching with protein flagellin. The extracellular antimicrobial protein of strain CMN1308 display four bands after urea-Tricine-SDS-PAGE, but after mass spectrometry analysis only two bands were identified. Band “A” with a maximum ion peak at M/Z of 1926 and molecular weight of 49.8 kDa, aligned with NCBI database, matching with DLDH (dihydrolipoamide dehydrogenase enzyme). Band “D” show the maximum ion peak at M/Z of 2936 and molecular weight of 22.4 kD, matching with a chitin binding protein. Thus, the strain CMN1308 has the potential to be developed as a commercial biological control agent for chestnut common pathogenic fungi.

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Parallel Reduction of Plasma Levels of High and Low Molecular Weight Kininogen in Patients with Cirrhosis

Thrombosis and Haemostasis ◽

10.1055/s-0037-1614849 ◽

1999 ◽

Vol 82 (11) ◽

pp. 1428-1432 ◽

Cited By ~ 9

Author(s):

Cheryl Scott ◽

Francesco Salerno ◽

Elettra Lorenzano ◽

Werner Müller-Esterl ◽

Angelo Agostoni ◽

...

Keyword(s):

Molecular Weight ◽

Liver Disease ◽

Liver Function ◽

Plasma Levels ◽

Plasma Concentrations ◽

Normal Subjects ◽

Low Molecular Weight ◽

Major Band ◽

Sds Page ◽

Normal Controls

SummaryLittle is known about the regulation of high-molecular-weight-kininogen (HK) and low-molecular-weight-kininogen (LK) or the relationship of each to the degree of liver function impairment in patients with cirrhosis. In this study, we evaluated HK and LK quantitatively by a recently described particle concentration fluorescence immunoassay (PCFIA) and qualitatively by SDS PAGE and immunoblotting analyses in plasma from 33 patients with cirrhosis presenting various degrees of impairment of liver function. Thirty-three healthy subjects served as normal controls. Patients with cirrhosis had significantly lower plasma levels of HK (median 49 μg/ml [range 22-99 μg/ml]) and LK (58 μg/ml [15-100 μg/ml]) than normal subjects (HK 83 μg/ml [65-115 μg/ml]; LK 80 μg/ml [45-120 μg/ml]) (p < 0.0001). The plasma concentrations of HK and LK were directly related to plasma levels of cholinesterase (P < 0.0001) and albumin (P < 0.0001 and P < 0.001) and inversely to the Child-Pugh score (P < 0.0001) and to prothrombin time ratio (P < 0.0001) (reflecting the clinical and laboratory abnormalities in liver disease). Similar to normal individuals, in patients with cirrhosis, plasma HK and LK levels paralleled one another, suggesting that a coordinate regulation of those proteins persists in liver disease. SDS PAGE and immunoblotting analyses of kininogens in cirrhotic plasma showed a pattern similar to that observed in normal controls for LK (a single band at 66 kDa) with some lower molecular weight forms noted in cirrhotic plasma. A slight increase of cleavage of HK (a major band at 130 kDa and a faint but increased band at 107 kDa) was evident. The increased cleavage of HK was confirmed by the lower cleaved kininogen index (CKI), as compared to normal controls. These data suggest a defect in hepatic synthesis as well as increased destructive cleavage of both kininogens in plasma from patients with cirrhosis. The decrease of important regulatory proteins like kininogens may contribute to the imbalance in coagulation and fibrinolytic systems, which frequently occurs in cirrhotic patients.

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Heterozygous Abnormal Fibrinogen Osaka III with the Replacement of γ Arginine-275 by Histidine Has an Apparently Higher Molecular Weight γ-Chain Variant

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646313 ◽

1992 ◽

Vol 68 (05) ◽

pp. 534-538 ◽

Cited By ~ 5

Author(s):

Nobuhiko Yoshida ◽

Shingi Imaoka ◽

Hajime Hirata ◽

Michio Matsuda ◽

Shinji Asakura

Keyword(s):

Molecular Weight ◽

Sodium Dodecyl Sulfate ◽

Gel Electrophoresis ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Tetraacetic Acid ◽

Fibrin Monomer ◽

Sds Page ◽

Thrombotic Tendency ◽

Chain Variant

SummaryCongenitally abnormal fibrinogen Osaka III with the replacement of γ Arg-275 by His was found in a 38-year-old female with no bleeding or thrombotic tendency. Release of fibrinopeptide(s) by thrombin or reptilase was normal, but her thrombin or reptilase time in the absence of calcium was markedly prolonged and the polymerization of preformed fibrin monomer which was prepared by the treatment of fibrinogen with thrombin or reptilase was also markedly defective. Propositus' fibrinogen had normal crosslinking abilities of α- and γ-chains. Analysis of fibrinogen chains on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the system of Laemmli only revealed the presence of abnormal γ-chain with an apparently higher molecular weight, the presence of which was more clearly detected with SDS-PAGE of fibrin monomer obtained by thrombin treatment. Purified fragment D1 of fibrinogen Osaka III also seemed to contain an apparently higher molecular weight fragment D1 γ remnant on Laemmli gels, which was digested faster than the normal control by plasmin in the presence of [ethy-lenebis(oxyethylenenitrilo)]tetraacetic acid (EGTA).

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Isolation and Structural Charaderization of a Potent Inhibitor of Coagulation Factor Xa from the Leech Haementeria ghilianii

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646610 ◽

1989 ◽

Vol 61 (03) ◽

pp. 437-441 ◽

Cited By ~ 28

Author(s):

Cindra Condra ◽

Elka Nutt ◽

Christopher J Petroski ◽

Ellen Simpson ◽

P A Friedman ◽

...

Keyword(s):

Molecular Weight ◽

Salivary Gland ◽

Amino Acid ◽

Amino Acid Sequence ◽

Western Blot ◽

Potent Inhibitor ◽

Factor Xa ◽

Coagulation Factor ◽

Sds Page ◽

Bovine Factor

SummaryThe present work reports the discovery and charactenzation of an anticoagulant protein in the salivary gland of the giant bloodsucking leech, H. ghilianii, which is a specific and potent inhibitor of coagulation factor Xa. The inhibitor, purified to homogeneity, displayed subnanomolar inhibition of bovine factor Xa and had a molecular weight of approximately 15,000 as deduced by denaturing SDS-PAGE. The amino acid sequence of the first 43 residues of the H. ghilianii derived inhibitor displayed a striking homology to antistasin, the recently described subnanomolar inhibitor of factor Xa isolated from the Mexican leech, H. officinalis. Antisera prepared to antistasin cross-reacted with the H. ghilianii protein in Western Blot analysis. These data indicate that the giant Amazonian leech, H. ghilianii, and the smaller Mexican leech, H. officinalrs, have similar proteins which disrupt the normal hemostatic clotting mechanisms in their mammalian host’s blood.

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Effect of Ocular Hypertension on D-β-Aspartic Acid-Containing Proteins in the Retinas of Rats

Journal of Ophthalmology ◽

10.1155/2019/2431481 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Takashi Kanamoto ◽

Takashi Tachibana ◽

Yasushi Kitaoka ◽

Toshio Hisatomi ◽

Yasuhiro Ikeda ◽

...

Keyword(s):

Mass Spectrometry ◽

Ocular Hypertension ◽

Aspartic Acid ◽

Atp Synthase ◽

Wistar Rats ◽

Protein Band ◽

Mass Spectrometry Analysis ◽

Liquid Chromatography Mass Spectrometry ◽

Spectrometry Analysis ◽

Sds Page

Purpose. To investigate the effect of ocular hypertension-induced isomerization of aspartic acid in retinal proteins. Methods. Adult Wistar rats with ocular hypertension were used as an experimental model. D-β-aspartic acid-containing proteins were isolated by SDS-PAGE and western blot with an anti-D-β-aspartic acid antibody and identified by liquid chromatography-mass spectrometry analysis. The concentration of ATP was measured by ELISA. Results. D-β-aspartic acid was expressed in a protein band at around 44.5 kDa at much higher quantities in the retinas of rats with ocular hypertension than in those of normotensive rats. The 44.5 kDa protein band was mainly composed of α-enolase, S-arrestin, and ATP synthase subunits α and β, in both the ocular hypertensive and normotensive retinas. Moreover, increasing intraocular pressure was correlated with increasing ATP concentrations in the retinas of rats. Conclusion. Ocular hypertension affected the expression of proteins containing D-β-aspartic acid, including ATP synthase subunits, and up-regulation of ATP in the retinas of rats.

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