Human isoforms of nucleoside diphosphate kinase, NDPK-HA and NDPK-HB, have been expressed in E. coli and purified. Their apparent molecular masses have been determined by FPLC gel filtration. Absolute molecular masses were measured by equilibrium ultracentrifugation and sedimentation coefficients determined from the sedimentation velocity. Under near-physiological conditions, NDPK-HA has a mass...

Enterotoxigenic Escherichia coli (ETEC) causes childhood diarrhea in developing countries. ETEC strains produce the heat-labile enterotoxin (LT) and/or heat-stable enterotoxins (ST) and encode a diverse set of colonization factors used for adherence to intestinal epithelial cells. We previously found that ETEC secretes a heat-stable protein we designated as ETEC Secreted Factor (ESF) that inhib...

A method for the recovery and fractionation of whey proteins from a whey protein concentrate (80%, w/w) by hydrophobic interaction chromatography is proposed. Standard proteins and WPC 80 dissolved in phosphate buffer with ammonium sulfate 1 M were loaded in a HiPrep Octyl Sepharose FF column coupled to a fast protein liquid chromatography (FPLC) system and eluted by decreasing the ionic streng...

A purification protocol that comprised ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on SP-Sepharose, and gel filtration by FPLC on Superdex 75 was complied to isolate two trypsin inhibitors from Phaseolus vulgaris cv "White Cloud Bean". Both trypsin inhibitors exhibited a molecular mass of 16 kDa and reduced the activit...

Two chitinases, designated PLC-A and PLC-B, were purified from the leayes of pokeweed (Pltytolacea americana) using DEAE-cellulose column chromatography followed by gel filtration on Sephadex G-75, hydrephobic column chromatography, and ion-exchange FPLC. PLC-A and PLC-B are acidic and basic proteins haying molecular masses of 2S and 29 kDa, and isoelectric points of 3.7 and 9.5, respectiyely. ...

The cysteine proteases of Paragonimus westermani metacercariae are involved in metacercarial excystment, host immune modulation, and possibly in tissue penetration. In order to clarify the origin of the enzymes, 28 and 27 kDa cysteine proteases in metacercarial excretory-secretory products were purified through the FPLC system using Mono Q column chromatography. The polyclonal antibodies to the...

This study is focussed on the possibility of producing a yeast culture with yellow wine lees as a substrate by solid-state fermentation (SSF). Results showed that a yeast count of 1.58 × 109 CFU/g was achieved by signal factor and orthogonal experiments. After fermentation, the starch content in the yeast culture reduced from 32.2% ± 0.5% to 7.5% ± 0.2%, and the contents of crude protein and pe...

In spite of the fact that commercial bromelain supplements are available in the market, to date, none of them are produced and formulated from recombinant forms. They are extracted and purified (often partially) from the stem and fruit of pineapple (Ananas comosus). This makes the production of bromelain very difficult, less reliable, often contaminated and expensive. In this study, a recombina...

A deoxyribonuclease distinct from the previously isolated asparagus ribosome-inactivating proteins, possessing a molecular weight of 30 kDa and requiring a pH of 7.5 for optimum hydrolytic activity toward herring sperm DNA, was isolated from Asparagus officinalis seeds. The isolation procedure involved extraction with saline, (NH(4))(2)SO(4) precipitation, ion-exchange chromatography on DEAE-ce...

A full-length human creatine kinase B (B-CK) cDNA was used to produce a recombinant baculovirus (AcDZl-BCK). Sf9 cells infected with this recombinant expressed a homodimeric protein composed of 43 kDa subunits which, under optimal condi­ tions, formed up to 30% of the total soluble cellular protein. Upon analysis by PAGE, zymogram assay and gel filtration chro­ matography the recombinant protei...