scholarly journals The effect of cambial zone isolation upon the autolytic system in maturing tracheids of pine (Pinus silvestris L.)

2014 ◽  
Vol 56 (3) ◽  
pp. 399-405 ◽  
Author(s):  
Jacek Zakrzewski ◽  
Krzysztof Rakowski
Keyword(s):  
Proteolytic Activity ◽  
Concentration Gradient ◽  
Specific Activity ◽  
Positional Information ◽  
Small Degree ◽  
Pinus Silvestris ◽  
Surgical Methods ◽  
Xylem Formation ◽  
Cambial Zone ◽  
Applied Auxin

The autolytic protease system in maturing tracheids of the main stem of <em>Pinus silvestris</em> was investigated after separation (using surgical methods) of the cambial zone from the layer of differentiating xylem, in combination with decapitation and IAA application. Separation of the cambium prevented autolysis of the protoplast in maturing tracheids, although the specific activity of proteases was little reduced. It was found that a radial or longitudinal concentration gradient of exogenously applied auxin was not responsible for autolysis, but that it could influence the level of extracted protein, and proteolytic activity. Similarly, decapitation modified, only to small degree, the effects of the cambium separation. Thus, the data from this experiment lead to the conclusion that integration of all cells in the region of xylem formation is a crucial factor for the start of autolytic protoplast breakdown. Possible involvement of auxin waves in the transfer of the positional information for this process is suggested.

A New Method for Plasminogen Standardization

1968 ◽  
Vol 20 (03/04) ◽  
pp. 548-554
Author(s):  
J Gajewski ◽  
G Markus
Keyword(s):  
Proteolytic Activity ◽  
Specific Activity ◽  
Molar Ratio ◽  
Sharp Transition ◽  
Equivalence Point ◽  
Constant Amount ◽  
Residual Level ◽  
Activity Measurements ◽  
Complete Saturation ◽  
Human Plasminogen

SummaryA method for the standardization of human plasminogen is proposed, based on the stoichiometric interaction between plasminogen and streptokinase, resulting in inhibition of proteolytic activity. Activation of a constant amount of plasminogen with increasing amounts of streptokinase yields linearly decreasing activities, as a function of streptokinase, with a sharp transition to a constant residual level. The point of transition corresponds to complete saturation of plasmin with streptokinase in a 1:1 molar ratio, and is therefore a measure of the amount of plasminogen present initially, in terms of streptokinase equivalents. The equivalence point is independent of the kind of protein substrate used, buffer, pH, length of digestion and, within limits, temperature. The method, therefore, is not subject to the variations commonly encountered in the usual determination based on specific activity measurements.

scholarly journals SELECTED PROTEOLYTIC ACTIVITY BY EXTRACTS OF DERMESTID LARVAE

2011 ◽  
Vol 19 (19) ◽  
pp. 79-83
Author(s):  
Lavinel G. IONESCU
Keyword(s):  
Enzyme Activity ◽  
Ammonium Sulfate ◽  
Proteolytic Activity ◽  
Specific Activity ◽  
Proteolytic Enzymes ◽  
High Specific Activity ◽  
Water Extract ◽  
Dermestes Maculatus ◽  
Crude Preparation

The larvae of the Beetle Dermestes maculatus De Geer can subsist on a diet consisting largely of protein. Studies have been undertaken to investigate the nature of proteolytic enzymes. A water extract of the larvae yielded a crude preparation that hydrolyzes gelatin, bide powder, hemoglobin substrate, benzoyl-DL-arginine p-nitroamilide, and glutaryl-L-phenylalanine p-nitroanilide. Enzyme activity was found in a non-dialyzable, heat- and acid0labile portion of the extract yielded two fractions with high specific activity towards gelatin. These are precipitated between 40% to 60% saturation of ammonium sulfate and 60% to 80% saturation. The higher specific activity was observed in the 40%-60% fraction. These results suggest that the larvae of these dermestids contain proteolytic enzymes with actions similar to mammalian trypsin and chymotrypsin. The results also suggest that other proteolytic enzymes may be present as well.

Different contributions of pannier and wingless to the patterning of the dorsal mesothorax of Drosophila

Development ◽  
1999 ◽  
Vol 126 (16) ◽  
pp. 3523-3532 ◽  
Author(s):  
M.J. Garcia-Garcia ◽  
P. Ramain ◽  
P. Simpson ◽  
J. Modolell
Keyword(s):  
Transcription Factor ◽  
Concentration Gradient ◽  
Positional Information ◽  
Secreted Protein ◽  
Expression Domain ◽  
Similar Role ◽  
Finger Protein ◽  
Proneural Cluster ◽  
Gata Family ◽  
Permissive Role

In Drosophila, the GATA family transcription factor Pannier and the Wnt secreted protein Wingless are known to be important for the patterning of the notum, a part of the dorsal mesothorax of the fly. Thus, both proteins are necessary for the development of the dorsocentral mechanosensory bristles, although their roles in this process have not been clarified. Here, we show that Pannier directly activates the proneural genes achaete and scute by binding to the enhancer responsible for the expression of these genes in the dorsocentral proneural cluster. Moreover, the boundary of the expression domain of Pannier appears to delimit the proneural cluster laterally, while antagonism of Pannier function by the Zn-finger protein U-shaped sets its limit dorsally. So, Pannier and U-shaped provide positional information for the patterning of the dorsocentral cluster. In contrast and contrary to previous suggestions, Wingless does not play a similar role, since the levels and vectorial orientation of its concentration gradient in the dorsocentral area can be greatly modified without affecting the position of the dorsocentral cluster. Thus, Wingless has only a permissive role on dorsocentral achaete-scute expression. We also provide evidence indicating that Pannier and U-shaped are main effectors of the regulation of wingless expression in the presumptive notum.

scholarly journals The possible relation between cytokinins and secondary xylem formation in Pinus silvestris. I. Seasonal correlations

2015 ◽  
Vol 48 (2) ◽  
pp. 295-303 ◽  
Author(s):  
Dorota B. Kubowicz
Keyword(s):  
Annual Ring ◽  
Secondary Xylem ◽  
Late Summer ◽  
Cambial Activity ◽  
Cytokinin Activity ◽  
Endogenous Cytokinin ◽  
Pinus Silvestris ◽  
Xylem Formation ◽  
Summer Maximum ◽  
Spring Maximum

The Seasonal dynamics of changes in the endogenous cytokinin level was investigated in the tissue of the stem cambial region, The results of the soybean test and Amaranthus test show that marked variations occur. in the course of the year in cytokinin activity in five fractions obtained from tissue of the cambial region. These variations characterized by a spring maximum and late-summer maximum may be correlated in time with changes in cambial activity and the course of annual ring differentiation in the pine stem during the vegetation season.

Single-Step Separation of Lactate Dehydrogenase Using Thiophilic Chromatography

1998 ◽  
Vol 63 (6) ◽  
pp. 851-856
Author(s):  
Milena Kmínková ◽  
Jiří Kučera
Keyword(s):  
Lactate Dehydrogenase ◽  
Proteolytic Activity ◽  
Cyprinus Carpio ◽  
Hydrophobic Interaction ◽  
Specific Activity ◽  
Hydrophobic Interaction Chromatography ◽  
Single Step ◽  
Hydrophobic Adsorption ◽  
Negative Adsorption ◽  
Final Purification

Lactate dehydrogenase (EC 1.1.1.27) from carp (Cyprinus carpio) hepatopancreas was purified by the single-step chromatography on thiophilic sorbent. Hydrophobic negative sorption was used as negative adsorption step for final purification. Final specific activity was 8.88 U/mg protein and the yield 84%. The enzyme is not adsorbed during hydrophobic interaction chromatography, but proteolytic activity is adsorbed completely on hydrophobic sorbent. Thus hydrophobic adsorption can be used as a prepurification step.

Characterization and Purification of Protease Extracted from Two Maturity Stages of ‘Noni’ (Morinda citrifolia L.) fruit

2014 ◽  
Vol 11 (2) ◽  
pp. 1 ◽  
Author(s):  
Normah Ismail ◽  
Nurulain Abd Razak
Keyword(s):  
Molecular Weight ◽  
Proteolytic Activity ◽  
Specific Activity ◽  
Morinda Citrifolia ◽  
Precipitation Method ◽  
Unripe Fruit ◽  
Maturity Stages ◽  
Plant Protease ◽  
Freeze Dried ◽  
And Storage

Protease was extracted from two maturity stages of noni fruits (Morinda citrifolia L.), unripe (stage 1) and ripe (stage 5). The crude extract was partially purified by acetone precipitation method followed by dialysis, gel filtration chromatography and freeze drying. Protein concentrations, proteolytic activity, molecular weight distribution, pH stability, temperature stability and storage efficiency of the resulting protease were evaluated. The unripe and ripe noni fruit contains 0.65 and 0.35% protein, respectively. Molecular weight of the proteases from both stages ranged approximately between 3 to 28 kDa based on the SDS-PAGE results. The optimum activity were at pH 7s and 6, temperatures of 40 and 50°C, respectively for proteases obtained from the unripe and ripe fruit. Analysis from the freeze dried protease indicated that protease from ripe noni fruits had higher protein concentration and specific activity compared to those from unripe fruit. However, it is more sensitive to pH and temperature and less stable during storage as it shows lower proteolytic activity compared to protease from unripe fruit. Based on its high proteolytic activity reaching up to 70.31 U/mg and storage stability (30% lost of activity), noni fruit could be an alternative source of plant protease.

MICROMICETES ASPERGILLUS RAPERI AND SAROCLADIUM STRICTUM AS PRODUCERS OF ENZYMES WITH UROKINASE-LIKE PLASMINOGEN ACTIVATOR ACTIVITY

2020 ◽  
pp. 228-230
Author(s):  
E. Kornienko ◽  
A. Osmolovskiy
Keyword(s):  
Plasminogen Activator ◽  
Proteolytic Activity ◽  
Specific Activity ◽  
High Specificity ◽  
Hemostasis System ◽  
Plasminogen Activator Activity

Data were obtained on the general proteolytic activity of Aspergillus raperi and Sarocladium strictum and on proteolytic activity in relation to the main proteins of the hemostasis system (specific activity). It has been shown that Sarocladium strictum is a more promising strain producing enzymes with urokinase-like plasminogen activator activity due to the high specificity of this activity.

Polarity of Xylem Formation in Isolated Stem Segments of Pinus silvestris

1978 ◽  
Vol 44 (3) ◽  
pp. 175-180 ◽  
Author(s):  
STEFAN ZAJACZKOWSKI ◽  
J. A. ROMBERGER
Keyword(s):  
Pinus Silvestris ◽  
Xylem Formation ◽  
Stem Segments

scholarly journals Association of a protease (plasminogen activator) with a specific membrane fraction isolated from transformed cells.

1976 ◽  
Vol 71 (2) ◽  
pp. 472-486 ◽  
Author(s):  
J P Quigley
Keyword(s):  
Plasminogen Activator ◽  
Malignant Transformation ◽  
Membrane Fraction ◽  
Specific Activity ◽  
Gradient Centrifugation ◽  
Surface Membrane ◽  
Cellular Protein ◽  
Small Degree ◽  
Surface Proteins ◽  
Cytoplasmic Material

The intracellular distribution of specific protease, plasminogen activator (PA), has been examined in Rous sarcoma virus-transformed chick embryo fibroblasts (RSV-CEF). Cellular homogenates were fractionated by differential centrifugation followed by sucrose gradient centrifugation. The activities and the percent distribution of a series of marker enzymes, specific for different subcellular organelles, were compared to those of PA. Normal CEF have been similarly fractionated and the relatively low amount of PA activity present in these cells has been analyzed in terms of its subcellular distribution. A membrane fraction was isolated from the RSV-CEF that contained the bulk of the PA activity and less than 8% of the total cellular protein. The specific activity of the PA in this fraction is 40-fold higher than that of a comparable fraction isolated from companion cultures of normal cells. This fraction contains little or no nuclear and cytoplasmic material and is contaminated only to a relatively small degree with mitochondria, lysosomes, endoplasmic reticulum. Significant amounts of a putative Golgi membrane marker are present in this fraction. The relatively high specific activities of Na+,K+-ATPase, 5'-nucleotidase, and [3H]fucose indicate that the fraction is enriched in surface membrane. Further purification of the fraction by equilibrium centrifugation on shallow sucrose gradients reduces further the contaminating activities and results in a PA distribution that closely parallels the distribution of the membrane enzyme, 5'-nucleotidase. PA was not released from its membrane association by hypotonic and hypertonic extraction and ultrasonication, while granule-bound enzymes were released by these treatments. The PA activity from hamster SV40 cells fractionated the same way as that of RSV-CEF. These results suggest that a protease that is dramatically enhanced upon malignant transformation is associated with "plasma membrane-like" elements of the cell and may serve as an intrinsic modifier of cell surface proteins after malignant transformation.

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