Further evidence for an active site polypeptide of galactosyl transferase

1993 ◽  
Vol 13 (5) ◽  
pp. 265-273
Author(s):  
Y. Plancke
Keyword(s):  
Molecular Weight ◽  
Peptide Mapping ◽  
Low Molecular Weight ◽  
Transferase Activity ◽  
Molecular Weight Range ◽  
Galactosyl Transferase ◽  
Activity Peak ◽  
Hydrophobic Peptide ◽  
Covalent Structure ◽  
Triton X

In a previous report it was shown that galactosyl transferase activity after blotting from acrylamide gel was present in a molecular weight range of less than 14 kDa, in Triton X-100 (1). Molecular sieve chromatography on Superose 12, in the presence of Triton X-100, gave the same result. The low molecular weight activity peak was eluted together with peptides as a part of the covalent structure of the enzyme or as absolutely requires effectors. Peptide mapping showed a new poly-lysine-like peptide and a new hydrophobic peptide in this low molecular weight activity peak as effectors of the enzyme inside its hydrophobic environment.

scholarly journals Experimental and Theoretical Studies of Carboxylic Polymers with Low Molecular Weight as Inhibitors for Calcium Carbonate Scale

Crystals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 406 ◽  
Author(s):  
Yuwei Zuo ◽  
Wenzhong Yang ◽  
Kegui Zhang ◽  
Yun Chen ◽  
Xiaoshuang Yin ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Calcium Carbonate ◽  
Normal Growth ◽  
Dynamics Simulation ◽  
Low Molecular Weight ◽  
X Ray Diffraction ◽  
Crystal Surfaces ◽  
Molecular Weight Range ◽  
Scale Inhibition ◽  
Diffraction Patterns

Poly acrylic acid (PAA) and polyepoxysuccinic acid (PESA) were investigated as scale inhibitors. The static experiments certified that PAA was superior to PESA for the inhibition of calcium carbonate in the low molecular weight range. The X-ray diffraction patterns suggest that the effect of PAA on the calcite (1 0 4) and (1 1 0) crystal plane was more obvious. Scanning electron microscopy was used to study the surface morphology of the depositions, which indicated that the addition of scale inhibitors could disturb the normal growth of CaCO3 scale. The transmittance ratio of ferric oxide demonstrated that PAA had a better dispersion performance than PESA. The molecular dynamics simulation and quantum calculation were selected to theoretically explore the mechanism and structure of scale inhibitors, indicating that the interaction of PAA with (1 0 4) and (1 1 0) calcite crystal surfaces was stronger than PESA. In addition, the results indicated that the PAA with negative charge more easily adsorbed free Ca2+ in the aqueous phase. Based on these observations, PAA exhibited better scale inhibition and dispersion effects than PESA in the case of low molecular weight.

PROTEOGLYCANS AND SULFATED PROTEINS OF PLATELETS: CHARACTERIZATION AND RESPONSE TO THROMBIN AND ADP

1987 ◽  
Author(s):  
B P Schick ◽  
C J Walsh ◽  
T Jenkins-West
Keyword(s):  
Molecular Weight ◽  
Guinea Pig ◽  
Platelet Activation ◽  
Negative Charge ◽  
Total Cell ◽  
Low Molecular Weight ◽  
Sds Page ◽  
Form Part ◽  
Triton X

The proteoglycans (PG) and sulfated proteins of guinea pig platelets were labeled in vivo by intraperitoneal injection of (35S)sulfate. At 3 days after injection, platelets contained 3 distinct populations of chondroitin-6-sulfate proteoglycans which together constitute about 65% of the cellular (35S) label. Most PG elute from a DEAE-Sephacel column with 4M Gdn HC1 (PG-1, 87%), and elute at Kav 0.12 on Sepharose CL-6B. The PG-1 can be resolved by SDS-PAGE into two fractions. The remainder (PG-2, 13%) elutes from the DEAE-Sephacel column with 4M Gdn HCl/2% Triton X-100 or 2% CHAPS, and has a Kav of 0.07 on Sepharose CL-6B. About 20-25% of the cell (35S) label elutes from DEAE-Sephacel in the wash-through or with 0.23M NaCl, and can be resolved by SDS-PAGE into at least 8 distinct bands which we have tentatively characterized as sulfated glycoproteins. The remainder of the (35S) is in low molecular weight (LMW) material which does not adhere to DEAE-Sephacel and has not been further characterized.Platelets were treated with either thrombin or ADP, and the cells were then separated from the supernatant by centrifugation. The radiolabeled molecules in the supernatant and the cells were analyzed by DEAE-Sephacel and Sepharose CL-6B column chromatography. About 65% of the total cell (35S) was released from the cells by thrombin. Most of this radiolabel adhered to the DEAE-Sephacel column, and was found to be PG-1. The remainder of the released (35S) was about half the LMW material. In contrast, only 10-15% of the (35S)labeled material retained by the cells adhered to DEAE-Sephacel and was found to be PG-2. The remainder of the (35S)-labeled material retained by the platelets was the sulfated proteins and the LMW material. ADP caused release of about 15% of the (35S), and this was found to be in part PG-1 and in part the LMW material, but not PG-2. None of the (35S)-labeled molecules appeared to be degraded during platelet activation. We suggest that the PG-1 represent the a-granule and PG-2 the membrane proteoglycans. The sulfated proteins have not been described previously. Their role is not known, but we hypothesize that they may form part of the negative charge of the glycocalix and thus be part of the reactive surface of the platelet.

scholarly journals Identification of cytoskeletal components involved in attachment of L929 cells and macrophages to polystyrene.

1981 ◽  
Vol 89 (3) ◽  
pp. 691-694 ◽  
Author(s):  
K W Lanks ◽  
N W Chin
Keyword(s):  
Molecular Weight ◽  
Peptide Mapping ◽  
Limited Proteolysis ◽  
Detailed Examination ◽  
Peritoneal Macrophages ◽  
Intimate Contact ◽  
L929 Cells ◽  
Molecular Weights ◽  
Murine Peritoneal Macrophages ◽  
Triton X

We have previously shown that lactoperoxidase (LPO) covalently coupled to polystyrene tissue culture flasks can be used to radioiodinate monolayer cell proteins that come into intimate contact with the LPO-polystyrene surface. These studies have now been extended to include a detailed examination of the class of iodinated polypeptides migrating with apparent molecular weights of 50,000 and 55,000 in SDS polyacrylamide gels. Whereas in cultured L929 cells the 55,000 band is predominantly iodinated, in thioglycollate-activated murine peritoneal macrophages the 55,000 and 50,000 bands are of equal intensity. It is possible that the marked degree of exposure of the 50,000 mol wt polypeptide to immobilized LPO is related to the unique strength of macrophages attachment. After labeling of both L929 cells and macrophages with immobilized LPO, all polypeptides in this molecular weight region were subjected to peptide mapping by simultaneous limited proteolysis and electrophoresis in a second SDS polyacrylamide slab gel. The results clearly show that the two major polypeptides in this region are identical within the limits of resolution of this technique. The 55,000 mol wt polypeptide can also be identified in Triton X-100 cytoskeletons from L929 cells after labeling with soluble LPO either before or after detergent lysis. We conclude that this cell surface polypeptide is in continuity with the cytoskeleton and is preferentially exposed to the substratum during attachment to polystyrene.

Identification of luteinizing hormone receptor binding inhibitor in bovine corpora lutea

1995 ◽  
Vol 132 (2) ◽  
pp. 213-217 ◽  
Author(s):  
Premila Rathnam ◽  
Shou-qing Lin ◽  
Brij B Saxena
Keyword(s):  
Molecular Weight ◽  
Luteinizing Hormone ◽  
Receptor Binding ◽  
Hormone Receptor ◽  
Luteinizing Hormone Receptor ◽  
Low Molecular Weight ◽  
Corpora Lutea ◽  
Molecular Weight Range ◽  
Lh Receptor ◽  
Weight Range

Rathnam P, Lin S, Saxena BB. Identification of luteinizing hormone receptor binding inhibitor in bovine corpora lutea. Eur J Endocrinol 1995;132:213–17. ISSN 0804–4643 A 7000 g supernatant, obtained during the purification of luteinizing hormone (LH) receptor from bovine corpora lutea homogenate, was concentrated by ultrafiltration. The filtrate, containing < 50 000 molecular weight material, exhibited LH receptor binding inhibitor (LH-RBI) activity. The filtrate was ultrafiltered sequentially through Amicon PM-10, PM-30 and UM-2 filters to yield a LH-RBI-containing fraction in the higher molecular weight range of 30 000–10 000 and a LH-RBI-containing fraction in the lower molecular weight range of 10 000–1000. The higher molecular weight LH-RBI fraction was purified on Sephadex G-25 and the lower molecular weight LH-RBI fraction was purified on Sephadex G-50. Both the high- and the low-molecular-weight LH-RBI species inhibited the binding of 125I-labeled human chorionic gonadotropin (hCG) to bovine corpora lutea and to rat Leydig cell membrane receptors. Similarly, the production of testosterone by hCG-stimulated rat Leydig cells was inhibited in a dose–response manner by both the high- and the low-molecular-weight LH-RBI species. The LH-RBI activity in the low-molecular-weight species was stable at 4°C for up to 6 months and at temperatures up to 90°C for 15 mins, whereas the LH-RBI activity of the high-molecular-weight species was stable at 4°C for 15 months and unstable at 60°C after 15 min. The 7000 g supernatant provided a much-needed source to obtain larger than previously reported quantities of LH-RBI for isolation as well as for structure and function studies. Brij B Saxena, Cornell Univ. Medical College, Rm A-267, 1300 York Ave, New York, NY 10021, USA

Low Molecular Weight Heparin Is Responsible for the Anti-Xa Activity of Desmin 370

1996 ◽  
Vol 75 (02) ◽  
pp. 286-291 ◽  
Author(s):  
David Brieger ◽  
Joan Dawes
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight Heparin ◽  
Anticoagulant Activity ◽  
Factor Xa ◽  
Biologically Active ◽  
Low Molecular Weight ◽  
Dermatan Sulphate ◽  
Molecular Weight Range ◽  
Sulphated Glycosaminoglycan

SummaryDermatan sulphate does not catalyse the inactivation of factor Xa. However, the low molecular weight (LMW) dermatan sulphate Desmin 370 has been shown to generate circulating anti-Xa activity following administration to humans. Using a single batch of Desmin 370, we measured 3 U/mg of anti-Xa activity by amidolytic assay in vitro. The material responsible for this activity had a lower molecular weight range (6000 and 1800 Da) than Desmin 370 and was more highly sulphated than the bulk of the drug. Heparinase digestion of Desmin 370 eliminated 90% of the in vitro anti-Xa activity without significantly interfering with its ability to potentiate inactivation of thrombin by HCII, suggesting that the anti-Xa activity is not due to dermatan sulphate and is probably heparin. When 125I-labelled Desmin 370 together with 40 mg/kg carrier drug was administered intravenously to a rabbit, anti-Xa activity was readily detectable in the plasma for up to 10 h and had a longer half-life than the sulphated radiolabel. Most of this anticoagulant activity was recovered from the plasma by Polybrene affinity chromatography and was probably a sulphated glycosaminoglycan. Administration of the heparinase-digested drug to a rabbit resulted in 70% less anti-Xa activity than the undigested drug. We conclude that Desmin 370 contains detectable quantities of biologically active low molecular weight heparin, which is responsible for persistent anti-Xa activity following intravenous administration.

A Novel Preparation of Nanocapsules from Alginate-Oligochitosan

2007 ◽  
Vol 7 (12) ◽  
pp. 4571-4574 ◽  
Author(s):  
Ting Wang ◽  
Zhangqi Feng ◽  
Nongyue He ◽  
Zhifei Wang ◽  
Song Li ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Efficient Method ◽  
Low Molecular Weight ◽  
Optimal Conditions ◽  
Emulsion System ◽  
Micro Emulsion ◽  
Triton X

A novel, simple and efficient method to prepare a new kind of nanocapsules in a demulsifying W/O micro-emulsion system from low molecular weight (MW) alginate and oligochitosan (OCS) was reported. Low MW alginate (LMWALG) was prepared by radiation of UV in the presence of cathode ion, OCS were used as anode ions. The composition for LMWALG demulsifying W/O micro-emulsion system is 50.75% (wt) of cyclohexane, 17.67% (Triton X-100 + n-pentanol), and 31.58% of LMWALG gelatum, while that for OCS one is 48.21% of cyclohexane, 16.09% (Triton X-100 + n-pentanol), and 35.70% OCS aqueous solution. The preparation of nanocapsules was optimized based on the above compositions for the MW of alginate, the MW of OCS, concentration of OCS and the encapsulation time. Ultimately the MW of LMWALG is 0.13 million and that of OCS is 3000 with a concentration of 1%, encapsulating for 30 min, under the above optimal conditions nanocapsules were formed in diameter of 136 nm.

scholarly journals Purification and characterization of a low molecular weight xylanase from solid-state cultures of Aspergillus fumigatus Fresenius

1999 ◽  
Vol 30 (2) ◽  
pp. 114-119 ◽  
Author(s):  
Claudio Henrique Cerri e Silva ◽  
Jurgen Puls ◽  
Marcelo Valle de Sousa ◽  
Edivaldo Ximenes Ferreira Filho
Keyword(s):  
Molecular Weight ◽  
Solid State ◽  
Aspergillus Fumigatus ◽  
Gel Filtration ◽  
Low Molecular Weight ◽  
Transferase Activity ◽  
Purification And Characterization ◽  
Apparent Homogeneity ◽  
Sds Page

A xylan-degrading enzyme (xylanase II) was purified to apparent homogeneity from solid-state cultures of Aspergillus fumigatus Fresenius. The molecular weight of xylanase II was found to be 19 and 8.5 kDa, as estimated by SDS-PAGE and gel filtration on FPLC, respectively. The purified enzyme was most active at 55 °C and pH 5.5. It was specific to xylan. The apparent Km and Vmax values on soluble and insoluble xylans from oat spelt and birchwood showed that xylanase II was most active on soluble birchwood xylan. Studies on hydrolysis products of various xylans and xylooligomers by xylanase II on HPLC showed that the enzyme released a range of products from xylobiose to xylohexaose, with a small amount of xylose from xylooligomers, and presented transferase activity.

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