Post-proline endopeptidase, further characterization of the enzyme from pig kidneys

A post-proline endopeptidase (EC 3.4.21.26) was isolated from pig kidneys using a modified method described earlier. The enzyme was further purified by ion exchange chromatography on DEAE-Sephacel. The final product contained about 95% of post-proline endopeptidase. The enzyme molecule consisted of one peptide chain with a relative molecular mass of 65 600 to 70 000, containing a large proportion of acidic and alifatic amino acids (glutamic acid, aspartic acid and leucine) and the N-terminus was formed by aspartic acid or asparagine. In order to prevent losses of enzyme activity, thiol compounds has to be added.

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Purification and Characterization of Laccase from Curvularia trifol

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.113-116.2215 ◽

2010 ◽

Vol 113-116 ◽

pp. 2215-2219

Author(s):

Jie Zhang ◽

Jing Ren ◽

Yang Yu ◽

Bin Song Wang

Keyword(s):

Enzyme Activity ◽

Ion Exchange ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Recycling Rate ◽

Relative Molecular Mass ◽

Optimal Temperature ◽

Purification And Characterization ◽

Alizarin Red

Electrophoretic pure lacquer enzymes were obtained from the thick enzyme of Gladiolus Curvularia trifol with grading precipitation and DEAE2-Cellulose ion exchange chromatography. The overall recycling rate of enzyme activity was 14.97% and the purification reached 2.96 times. The relative molecular mass of enzyme was 92.3Kda. The optimal temperature and pH were 40°C and 3.5, respectively. The Km of ABTS catalyzed by laccase was 1.11× 10- 5mol L-1. Alizarin red and Congo red could be degradated by purified laccase effectively without the participation of small molecule amboceptor. Alizarin red could be degradated by 80% with its being affected by 1000U/L of enzyme activity for 70h, which revealed the huge potentiality of Gladiolus Curvularia trifol and laccase in the degradation of dye.

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Preparation and Characterization of NH2-Terminal Fibrinogen Bβ Fragments from N-DSK of Human Fibrinogen

Thrombosis and Haemostasis ◽

10.1055/s-0038-1660999 ◽

1984 ◽

Vol 51 (01) ◽

pp. 016-021 ◽

Cited By ~ 2

Author(s):

S Birken ◽

G Agosto ◽

B Lahiri ◽

R Canfield

Keyword(s):

High Performance ◽

Gel Filtration ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Reverse Phase ◽

Human Fibrinogen ◽

Human Volunteers ◽

Cnbr Cleavage ◽

Two Peaks

SummaryIn order to investigate the early release of NH2-terminal plasmic fragments from the Bβ chain of fibrinogen, substantial quantities of Bβ 1-42 and Bβ 1-21 are required as immunogens, as radioimmunoassay standards and for infusion into human volunteers to determine the half-lives of these peptides. Towards this end methods that employ selective proteolytic cleavage of these fragments from fibrinogen have been developed. Both the N-DSK fragment, produced by CNBr cleavage of fibrinogen, and Bβ 1-118 were employed as substrates for plasmin with the finding of higher yields from N-DSK. Bβ 1-42 and Bβ 1-21 were purified by gel filtration and ion-exchange chromatography on SP-Sephadex using volatile buffers. When the purified preparation of Bβ 1-42 was chromatographed on reverse-phase high performance liquid chromatography, two peaks of identical amino acid composition were separated, presumably due either to pyroglutamate or to amide differences.

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Preparation and properties of three analogues of [5-leucine]enkephalin, substrates for enzyme conversion studies

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19851329 ◽

1985 ◽

Vol 50 (6) ◽

pp. 1329-1334

Author(s):

Jaroslav Vičar ◽

Linda Servítová ◽

Martin Flegel ◽

Karel Hauzer ◽

Tomislav Barth

Keyword(s):

High Pressure ◽

Liquid Chromatography ◽

Guinea Pig ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Guinea Pig Ileum ◽

Opioid Activity ◽

C Terminus ◽

N Terminus ◽

Fragment Condensation

Analogues of [5-Leu]enkephalin, prolonged by methionine on the N-terminus or, by lysine or methionine on the C-terminus were prepared by fragment condensation, purified by ion exchange chromatography or high-pressure liquid chromatography. The substances were characterised by their opioid activity in a test on guinea-pig ileum in comparison with the activity of [5-Leu]enkephalin.

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