The effect of acidic polysaccharides and prostaglandin-like substances isolated from Propionibacterium acnes on granulocyte chemotaxis.

Three acidic polysaccharide (AP) fractions and the prostaglandin-like substances (PLS) isolated from P. acnes were investigated regarding their chemotactic activities on polymorphonuclear leukocytes. Both AP's and PLS induced a significant chemotatic response, which suggests their involvement in inflammatory acne vulgaris.     

Alcohol dehydrogenase 2 is a major hepatic enzyme for human retinol metabolism

The metabolism of all-trans- and 9-cis-retinol/ retinaldehyde has been investigated with focus on the activities of human, mouse and rat alcohol dehydrogenase 2 (ADH2), an intriguing enzyme with apparently different functions in human and rodents. Kinetic constants were determined with an HPLC method and a structural approach was implemented by in silico substrate dockings. For human ADH2, the determined K_m values ranged from 0.05 to 0.3 μM and k_cat values from 2.3 to 17.6 min⁻¹, while the catalytic efficiency for 9-cis-retinol showed the highest value for any substrate. In contrast, poor activities were detected for the rodent enzymes. A mouse ADH2 mutant (ADH2Pro47His) was studied that resembles the human ADH2 setup. This mutation increased the retinoid activity up to 100-fold. The K_m values of human ADH2 are the lowest among all known human retinol dehydrogenases, which clearly support a role in hepatic retinol oxidation at physiological concentrations. Received 12 October 2006; received after revision 6 December 2006; accepted 8 January 2007     

Prostaglandin-like substances inPropionibacterium acnes. IV. Effect on isolated human vessels

Summary The present study demonstrates a powerful vasoconstrictor activity of prostaglandin-like substances (PLS), extracted fromP. acnes, on human blood vessels. PLS is about equipotent to PGE₂ in its effect on human umbilical vessels, but the contractile response pattern is different. PLS therefore seems to have specific and different physiological characteristics.     

Proteases of Antarctic krill—a new system for effective enzymatic debridement of necrotic ulcerations

Summary The Antarctic krill (Euphausia superba) possesses an over-dimensioned digestive system, which is of vital importance for the survival of this euphaucean shrimp in the extreme marine environment. The isolated enzymes contain a well-balanced mixture of both endo- and exopeptidases, assuring fast and complete breakdown of proteinaceous material. These unique properties have now been shown to be extremely valuable for the effective removal of necrotic debris, fibrin or blood crusts in vitro. Therefore the krill enzymes should be considered as an important resource in the future management of necrotic wounds.     

Biosynthesis of deuteriated amino acids byCandida lipolytica

Summary Biosynthesis of a whole series of deuteriated amino acids has been carried out, by cultivation of the yeastCandida lipolytica in an artificial medium composed of a deuterio-alkane, heavy water, water and some mineral salts.Acknowledgments. This work has been carried out with the aid of grants from The Swedish Medical Research Council. Thanks are due to Mr Nils Engström for his skilful technical assistance during the yeast growth, and to Mrs Monica Olsson for the Moore-Stein analysis.     

Prostaglandin-like substances inPropionibacterium acnes. V. Activity profiles using cascade superfusion bioassay and platelet aggregation

Summary The activity spectrum of prostaglandin-like substances (PLS) fromP. acnes was investigated with cascade superfusion technique and by platelet aggregation assay. The biological activity of PLS resembles that of PGI₂: both relax bovine coronary artery, rabbit mesentric and coeliac arteries; both contract the rat stomach strip as well as both typically inhibit spontaneous movements of isolated guinea pig ileum. Also, similarly to PGI₂, PLS inhibits platelet aggregation regardless the inducer used. However, PLS possesses a specific antiaggregatory pattern on platelet, which indicates that these compounds are not indentical with primary prostaglandins or PGI₂.     

Debriding ability of a novel multi-enzyme preparation isolated from Antarctic krill (Euphausia superba)

Summary The wound-debriding activity of various types of proteolytic enzymes and proteases from Antarctic krill (multi-enzyme system consisting of both endo- and exopeptidases) was evaluated. The results, based on the enzymatically acieved weight reduction of a necrotic animal material (excised rat skin) in vitro, clearly showed that the multi-enzyme system (krill) had a higher degrading activity than the single enzyme preparation, or that with only a few enzymes. The debriding effect of the krill enzymes was markedly related to the enzyme concentration, resulting in 70–100% substrate degradation after 24 h. The digesting capacity of trypsin reached about 50%, but an increase in concentration of this enzyme did not substantially influence its overall activity. The effect of streptokinase-streptodornase, collagenase and plasmin-desoxyribonuclease was weak (10–20% digested).