Polyamines Affect Activity of Aminopeptidases from Lactobacillus sake

Abstract

The effects of polyamines (agmatine, cadaverine, putrescine, spermidine and spermine) on the activity of the main aminopeptidases (AP I and AP II) from Lactobacillus sake were determined. Concentrations in the range of 1 mM caused 6-25% inhibition of AP I except for spermine (45% inhibition). Higher polyamine levels (5-10 mM), except for putrescine, exerted a stronger inhibition (20-60%) on AP I. Agmatine and putrescine also reduced AP II activity (6-25%) at concentrations of 0.1-10 mM while cadaverine did not have a notable effect. Spermidine and spermine stimulated (15-70%) the activity of AP II at concentrations Ͼ1 mM. Thus, control of polyamine levels is important because they are a potential hazard for human health and also because of their effects on aminopeptidase activity.

Effect of Lactobacillus-protective cultures with bacteriocin-like inhibitory substances' producing ability on microbiological, chemical and sensory changes during storage of refrigerated vacuum-packaged sliced beef

“…The observed nonsignificant difference between the proteolysis degrees of samples Ls4808 and S+C could be attributed to microbial proteolysis caused by the Lact. sakei 4808 strain, as this strain has been confirmed to contain several peptidases and proteases (Sanz and Toldrá 1997a,b, 2001, 2002; Sanz and Toldrá 1998; Sanz et al. 1998) as well as to exhibit in vitro proteolytic action on both myofibrillar and sarcoplasmic proteins of muscle (Fadda et al.…”

Hydrolysis of Pork Muscle Sarcoplasmic Proteins by Lactobacillus curvatus and Lactobacillus sake

“…Aminopeptidase activity was measured against several aminoacyl-7-amido-4methyl coumarin (AMC) derivatives (L-Ala-, L-Lys-, L-Ser-, L-Phe-, L-Val-, L-Arg-, L-Gly-, L-Leu-, L-Tyr-, L-Pro-, and L-Pyr-AMC [Sigma]) and L-Glu-1-4-pnitroanilide (Fluka Biochemika, Buchs, Switzerland) according to the method of Sanz and Toldrá (26,27). Reaction mixtures were incubated at 37°C for 15 min, except for the chromogenic substrate, which was incubated for 1 h. One unit of activity was defined as described above, and aminopeptidase activity was expressed as units per milligram of protein.…”

“…However, a detailed study of their proteolytic systems is lacking, and only a dipeptidase (21), a tripeptidase (25), and an aminopeptidase (26) of L. sake have been purified and characterized. The activities of those purified peptidases have also been studied under the effects of curing agents and other technologic factors involved in the manufacture process (27)(28)(29). Nevertheless, a few studies have dealt with the real effects of proteolytic enzymes on muscle proteins and derived peptides.…”