Primary structure of three peptides at the catalytic and allosteric sites of the fructose-1,6-bisphosphate-activated pyruvate kinase from Escherichia coli.

Three peptides containing 6-pyridoxyllysine have been isolated from the tryptic digest of the allosteric fructose-1,6-bisphosphate-dependent pyruvate kinase from Escherichia coli, which had been almost completely inactivated with pyridoxal 5'-phosphate. The labelled peptides have been sequenced. The comparison of their sequences with the primary structure of the cat muscle pyruvate kinase allowed to state that peptide I fits the region spanning residues 423-438 (53% identity), peptide II corresponds to residues 442-457 (44% identity) and peptide III encompasses residues 342-368 (70% identity).

Reactivity of the fructose 1,6-bisphosphate-activated pyruvate kinase from Escherichia coli with pyridoxal 5'-phosphate.

The allosteric fructose 1,6-bisphosphate-activated pyruvate kinase from Escherichia coli was modified with pyridoxal 5'-phosphate in the presence and in the absence of phosphoenolpyruvate, fructose 1,6-bisphosphate, MgADP and MgATP. In all cases a time-dependent inactivation was observed, but the rate and the extent of inactivation varied according to the conditions used. The kinetic properties of the partially inactivated enzyme were differently modified by addition of substrates and effectors to the modification mixture, the parameters mostly affected being those concerning fructose 1,6-bisphosphate.

[Acute pulmonary edema due to hyperperfusion: experimental observations in the dog].

A condition of acute pulmonary edema was obtained experimentally in the dog, perfusing the lower lobe of the left lung by a roller pump with compatible canine plasma. The edema develops contemporarily to the increase of pressure in the pulmonary artery and the interstitial tissue: it diffuses principally in the interstitial tissue, while after clamping the pulmonary veins it is observed also inside the alveoli.

Influence of fibronectin on the fibrillogenesis of type I and type III collagen.

The in vitro self-assembly of type I and type III calf skin collagen in the presence of fibronectin was studied turbidimetrically. Fibronectin delayed the fibrillogenesis of type III collagen but accelerated that of type I collagen. The effect of fibronectin was concentration-dependent.

Rapid detection of herpes simplex virus in clinical specimens by centrifugation and immunoperoxidase staining.

The effect of immunoperoxidase staining and centrifugation on the sensitivity and rapidity of herpes simplex virus detection in mink lung cell cultures was determined with 730 clinical specimens. In standard tube cultures, the use of immunoperoxidase staining resulted in detection of 31 (91%) of 34 positive cultures after overnight incubation, compared with 25 (74%) detected without the stain (P less than 0.05).

A simple procedure for the purification of neutral salt soluble type I collagen from skin.

Intact monomeric type I collagen was purified from fetal bovine skin by a simple and time saving procedure. Saline precipitates of mixed skin collagens, in 4 M NaCl, were extracted with a limited volume of dilute acetic acid, taken in the proportion of 1 ml per g of original wet skin; NaCl in the precipitate was not removed by dialysis. The salt concentration in the extraction medium in the above conditions, selectively solubilized type I collagen.

Conformation and kinetic properties of photosynthetic glyceraldehyde-3-phosphate dehydrogenase "in vivo".

Photosynthetic GAPDH has been studied in chloroplast extracts, obtained in presence of physiological concentrations of NADP and NAD. The enzyme is shown to have a molecular weight of 600,000, on the basis of zymograms obtained after electrophoresis on polyacrylamide gradient gels. Km values of 0.

Apparent subunit heterogeneity of NAD-dependent glyceraldehyde-3-phosphate dehydrogenase from spinach leaves.

NAD dependent glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.

Purification and properties of NAD+-dependent glyceraldehyde-3-phosphate dehydrogenase from spinach leaves.

An NAD+-dependent glyceraldehyde-3-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate:NAD+ oxidoreductase (phosphorylating), EC. 1.2.

Subunit structure and activity of glyceraldehyde-3-phosphate dehydrogenase from spinach chloroplasts.

Glyceraldehyde-phosphate dehydrogenase (D-glyceraldehyde-3-phosphate : NADP+ oxidoreductase (phosphorylating), EC 1.2.1.