The Effect of Solution Properties on the Photochemical Ability of Pulsed Light to Inactivate Soybean Lipoxygenase

2018 ◽  
Vol 14 (5-6) ◽  
Author(s):  
Abeer Alhendi ◽  
Wade Yang ◽  
Paul J. Sarnoski
Keyword(s):  
Thermal Treatment ◽  
Protease Inhibitors ◽  
Protease Activity ◽  
Photothermal Effect ◽  
Soybean Lipoxygenase ◽  
Solution Properties ◽  
Pulsed Light ◽  
Sds Page

AbstractInactivation of pure soybean lipoxygenase (LOX) by pulsed light (PL) technique was found to occur due to a photochemical effect, while inactivation of soybean LOX in a real food (soymilk) was due to the photothermal effect of PL. The effect of solution properties on the photochemical ability of PL to inactivate and degrade LOX was investigated. LOX was placed in different conditions and treated with PL at a 7 cm distance with different times. The result showed that LOX was less stable during PL operation at pH 9 compared with pH 6.8. Increasing LOX concentration, adding starch, and making a colored solution did reduce the photochemical ability of PL to inactivate LOX. PL and thermal treatment of partially purified LOX degraded the LOX band (measured by using SDS-PAGE) when no protease inhibitors were added. Controlling protease activity led to degradation of LOX by PL but not by thermal treatment.

Metalloproteases and egg-hatching in Pediculus humanus, the body (clothes) louse of humans (Phthiraptera: Insecta)

Parasitology ◽  
2007 ◽  
Vol 135 (1) ◽  
pp. 125-130 ◽  
Author(s):  
V. M. BOWLES ◽  
A. R. YOUNG ◽  
S. C. BARKER
Keyword(s):  
Protease Activity ◽  
The Body ◽  
Egg Hatching ◽  
Egg Hatch ◽  
Pediculus Humanus ◽  
Sds Page ◽  
Metalloprotease Inhibitors ◽  
Egg Shell ◽  
Ph Range

SUMMARYTo investigate the biochemical components of egg-hatch in the body louse, Pediculus humanus, egg-shell-washings (ESW) were collected during the first 2 h post-hatching and analysed by gelatin SDS-PAGE. These ESW contained proteases with molecular mass in the range of 25–100 kDa; the most abundant proteases were ~25 kDa. The 3 main regions of protease activity in the one-dimensional gelatin SDS-PAGE gels resolved to at least 23 distinct regions of protease activity when analysed by two-dimensional gelatin SDS-PAGE, with iso-electric points spread over the entire 3 to 10 pH range. Mechanistic characterization indicated that the ESW contained proteases of the metallo-class, inhibited by both 1,10-phenanthroline and EDTA. Several protease inhibitors were tested for their ability to inhibit louse egg-hatch in vitro. The metalloprotease inhibitor 1,10-phenanthroline and the aminopeptidase inhibitor bestatin significantly inhibited (P<0·05) louse egg-hatch (100% and 58%, respectively). The presence of metalloproteases at the time of egg-hatch and the inhibition of egg-hatch in P. humanus by metalloprotease inhibitors suggests a crucial role for these proteases in the hatching of this medically important parasite.

scholarly journals Different molecular forms of plasminogen and plasmin produced by urokinase in human plasma and their relation to protease inhibitors and lysis of fibrinogen and fibrin

1974 ◽  
Vol 143 (2) ◽  
pp. 273-283 ◽  
Author(s):  
Sten Müllertz
Keyword(s):  
Human Plasma ◽  
Protease Inhibitors ◽  
Gel Electrophoresis ◽  
Protease Activity ◽  
Gel Filtration ◽  
Molecular Forms ◽  
Crossed Immunoelectrophoresis ◽  
Low Concentrations ◽  
Α2 Macroglobulin ◽  
Esterase Inhibitor

Urokinase-activated human plasma was studied by gel electrophoresis, gel filtration, crossed immunoelectrophoresis and electroimmunoassay with specific antibodies and by assay of esterase and protease activity of isolated fractions. Urokinase induced the formation of different components with plasminogen+plasmin antigenicity. At low concentrations of urokinase, a component with a KD value of 0.18 by gel filtration and post β1 mobility by gel electrophoresis was detected. The isolated component had no enzyme or plasminogen activity. In this plasma sample fibrinogen was not degraded for 10h, but when fibrin was formed, by addition of thrombin, fibrin was quickly lysed, and simultaneously a component with a KD value of 0 and α2 mobility appeared, which was probably plasmin in a complex with α2 macroglobulin. This complex showed both esterase and protease activity. After gel filtration with lysine buffer of the clotted and lysed plasma another two components were observed with about the same KD value by gel filtration as plasminogen (0.35), but β1 and γ mobilities by gel electrophoresis. They appeared to be modified plasminogen molecules, and possibly plasmin with γ mobility. Similar processes occurred without fibrin at higher urokinase concentrations. Here a relatively slow degradation of fibrinogen was correlated to the appearance of the plasmin–α2 macroglobulin complex. The fibrin surface appeared to catalyse the ultimate production of active plasmin with a subsequent preferential degradation of fibrin and the formation of a plasmin–α2 macroglobulin complex. The gel filtration and electrophoresis of the plasma protease inhibitors, α1 antitrypsin, inter-α-inhibitor, antithrombin III, and C1-esterase inhibitor indicated that any complex between plasmin and these inhibitors was completely dissociated. The β1 and post β1 components appear to lack correlates among components occurring in purified preparations of plasminogen and plasmin.

Protease activities of Acanthamoeba polyphaga and Acanthamoeba castellanii

2006 ◽  
Vol 52 (1) ◽  
pp. 16-23 ◽  
Author(s):  
José de Jesús Serrano-Luna ◽  
Isaac Cervantes-Sandoval ◽  
Jesús Calderón ◽  
Fernando Navarro-García ◽  
Victor Tsutsumi ◽  
...  
Keyword(s):  
Protease Activity ◽  
Serine Proteases ◽  
Biochemical Characterization ◽  
Acanthamoeba Castellanii ◽  
Cysteine Proteases ◽  
Skin Lesions ◽  
Sds Page ◽  
Serine Protease Family ◽  
Proteolytic Activities ◽  
Amoebic Keratitis

Acanthamoeba spp. are free-living amoebae that cause amoebic granulomatous encephalitis, skin lesions, and ocular amoebic keratitis in humans. Several authors have suggested that proteases could play a role in the pathogenesis of these diseases. In the present work, we performed a partial biochemical characterization of proteases in crude extracts of Acanthamoeba spp. and in conditioned medium using 7.5% SDS–PAGE copolymerized with 0.1% m/v gelatin as substrate. We distinguished a total of 17 bands with proteolytic activity distributed in two species of Acanthamoeba. The bands ranged from 30 to 188 kDa in A. castellanii and from 34 to 144 kDa in A. polyphaga. Additionally, we showed that the pattern of protease activity differed in the two species of Acanthamoeba when pH was altered. By using protease inhibitors, we found that the proteolytic activities belonged mostly to the serine protease family and secondly to cysteine proteases and that the proteolytic activities from A. castellanii were higher than those in A. polyphaga. Furthermore, aprotinin was found to in hibit crude extract protease activity on Madin–Darby canine kidney (MDCK) monolayers. These data suggest that protease patterns could be more complex than previously reported.Key words: Acanthamoeba spp., amoebic keratitis, serine proteases, cysteine proteases, cytopathic effect.

Analysis of protease activity in human otitis media

1998 ◽  
Vol 119 (4) ◽  
pp. 346-351 ◽  
Author(s):  
Michael A. Avidano ◽  
Cheryl S. Cotter ◽  
Scott P. Stringer ◽  
Gregory S. Schultz
Keyword(s):  
Matrix Metalloproteinases ◽  
Tympanic Membrane ◽  
Protease Inhibitors ◽  
Otitis Media ◽  
Neutrophil Elastase ◽  
Alkaline Protease ◽  
Protease Activity ◽  
Serine Proteases ◽  
Specific Inhibitor ◽  
Bacterial Invasion

Cronic otitis media is a common problem associated with a nonintact tympanic membrane frequently involving Staphylococcus aureus and Pseudomonas aeruginosa. The virulence of Pseudomonas bacteria is related to the production of two matrix metalloproteinases, elastase and alkaline protease. Serine proteases, such as neutrophil elastase, are produced by the host inflammatory response. These proteases are thought to contribute to tissue destruction and assist bacterial invasion during infection. This preliminary study was done to identify protease activity in otorrhea samples from patients with otitis media and a nonintact tympanic membrane and to examine the ability of selective protease inhibitors to decrease protease activity. Ilomostat (galardin) is a synthetic, specific inhibitor of matrix metalloproteinases including P. aeruginosa elastase and alkaline protease, where-as α1-antitrypsin inhibits serine proteases including neutrophil elastase. Samples were collected and cultured from 20 patients with otorrhea resulting from tympanic membrane perforations or pressure-equalization tubes. A protease assay that used azocasein as the substrate was used to quantify protease activity, with and without addition of selective protease inhibitors. Cultures revealed P. aeruginosa alone in 7 samples, P. aeruginosa plus other organisms in 10, and S. aureus alone in 3. Protease activity was detected in 15 (75%) of the samples. A statistically significant ( p < 0.05) decrease in protease activity was seen with the addition of α1-antitrypsin or Ilomostat plus α1-antitrypsin, but not with Ilomostat alone. Analyzing the 10 samples with the highest protease activity, a statistically significant decrease in activity was seen with Ilomostat or αα1-antitrypsin alone and with both Ilomostat and α1-antitrypsin together. Bacteriologic type, source of sample, age and gender of the subject, and duration of infection were not significantly related to protease activity. This is the first study to quantify protease activity and inhibition by selective protease inhibitors in human otorrhea. Protease inhibitors effectively decrease protease activity in most cases and in addition to standard antibiotic therapy might prove beneficial in the treatment of otitis media with a nonintact tympanic membrane. This study supports future clinical investigations into the role of proteases and inhibition of protease activity in the treatment of otitis media.

scholarly journals Interplay between Single Resistance-Associated Mutations in the HIV-1 Protease and Viral Infectivity, Protease Activity, and Inhibitor Sensitivity

2011 ◽  
Vol 56 (2) ◽  
pp. 623-633 ◽  
Author(s):  
Gavin J. Henderson ◽  
Sook-Kyung Lee ◽  
David M. Irlbeck ◽  
Janera Harris ◽  
Melissa Kline ◽  
...  
Keyword(s):  
Protease Inhibitor ◽  
Protease Inhibitors ◽  
Protease Activity ◽  
Leukemia Virus ◽  
Fold Increase ◽  
Pleiotropic Effect ◽  
Viral Fitness ◽  
Resistance Mutations ◽  
Primary Resistance ◽  
Hiv 1

ABSTRACTResistance-associated mutations in the HIV-1 protease modify viral fitness through changes in the catalytic activity and altered binding affinity for substrates and inhibitors. In this report, we examine the effects of 31 mutations at 26 amino acid positions in protease to determine their impact on infectivity and protease inhibitor sensitivity. We found that primary resistance mutations individually decrease fitness and generally increase sensitivity to protease inhibitors, indicating that reduced virion-associated protease activity reduces virion infectivity and the reduced level of per virion protease activity is then more easily titrated by a protease inhibitor. Conversely, mutations at more variable positions (compensatory mutations) confer low-level decreases in sensitivity to all protease inhibitors with little effect on infectivity. We found significant differences in the observed effect on infectivity with a pseudotype virus assay that requires the protease to cleave the cytoplasmic tail of the amphotropic murine leukemia virus (MuLV) Env protein. Additionally, we were able to mimic the fitness loss associated with resistance mutations by directly reducing the level of virion-associated protease activity. Virions containing 50% of a D25A mutant protease were 3- to 5-fold more sensitive to protease inhibitors. This level of reduction in protease activity also resulted in a 2-fold increase in sensitivity to nonnucleoside inhibitors of reverse transcriptase and a similar increase in sensitivity to zidovudine (AZT), indicating a pleiotropic effect associated with reduced protease activity. These results highlight the interplay between enzyme activity, viral fitness, and inhibitor mechanism and sensitivity in the closed system of the viral replication complex.

Differences in induction of lysosomal protease activity by protease inhibitors in B16 melanoma cell lines

1989 ◽  
Vol 21 (2) ◽  
pp. 139-142 ◽  
Author(s):  
Nakao Hiroshi ◽  
Kurita Yoriyuki ◽  
Tsuboi Ryoji ◽  
Takamori Kenji ◽  
Ogawa Hideoki
Keyword(s):  
Protease Inhibitors ◽  
Cell Lines ◽  
Melanoma Cell ◽  
Protease Activity ◽  
B16 Melanoma ◽  
Lysosomal Protease ◽  
B16 Melanoma Cell ◽  
Melanoma Cell Lines

Characteristics of Soybean Meals by Solid State Fermentation Using Bacillus subtilis GA15

2013 ◽  
Vol 781-784 ◽  
pp. 1760-1764
Author(s):  
Xiao Jia Yang ◽  
Jin Shui Wang ◽  
Sen Yang
Keyword(s):  
Bacillus Subtilis ◽  
Solid State ◽  
Moisture Content ◽  
Solid State Fermentation ◽  
Protease Activity ◽  
Optimal Conditions ◽  
Sds Page

Characteristics of solid state fermentation for soybean meals were studied in present paper. Effects of different factors on protease activity and peptides content during fermentation, using Bacillus Subtilis GA15 were explored. Optimal conditions of moisture content 50%, substrate height 2.5 cm at 36 °C for 72 h of incubation were obtained. Peptide content could be up to 14.37% in this condition. Moreover, the allergens in soybean meals were almost eliminated during fermentation according to SDS-PAGE profile.

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