Effect of Coagulants, Somatic Cell Enzymes, and Extracellular Bacterial Enzymes on Plasminogen Activation

Mastitis impact on technological properties of milk and quality of milk products—a review

“…It has a pH optimum around 7.5 (Bastian and Brown 1996;Fox and McSweeney 1996). In mastitis, increased SCC has been correlated with an increased plasmin activity (Albenzio et al 2005;Kalit et al 2002;Politis et al 1989a;Saeman et al 1988;Somers et al 2003) which can be explained by the conversion of plasminogen to plasmin (Verdi and Barbano 1991) and or by plasmin transport from blood (Politis et al 1989b). Conversion of plasminogen to plasmin can be induced by activators, whose levels increase due to the increase in epithelial barrier permability (Dano et al 1985) and to their synthesis by PMN (Moir et al 2001;Politis et al 1991).…”

Effects of somatic cell counts in milk on physical and chemical characteristics of yoghurt

“…On the other hand, Kohlmann, Nielsen, and Ladisch (1991) reported that addition of plasmin to milk submitted to the ultra-high-temperature process causes an increase of apparent viscosity of the product after 90 d of storage. Since somatic cells are related to conversion of plasminogen to plasmin in milk (Verdi & Barbano, 1991), the occurrence of age-thickening gelation processes associated with the plasmin content in milk could also be a possible explanation for the higher viscosity observed in yoghurt produced from milk with high SCC.…”

“…Proteolysis from plasmin comprises nearly 90% of total proteolysis in milk (Barry & Donnelly, 1981). Plasmin is generated from plasminogen, with conversion being more pronounced in milks with high SCC (Verdi & Barbano, 1991).…”

Atividade de plasmina e plasminogênio no leite longa vida com alta e baixa contagem de células somáticas durante o armazenamento

“…O plasminogênio, que também está presente no leite, pode ser prontamente ativado e convertido em plasmina (RICHARDSON, 1983). VERDI & BARBANO (1991) evidenciaram que as células somáticas apresentam esta capacidade de conversão, resultando em proteólise da caseína. Esse fato confirma a associação entre a alta contagem de células somáticas (CCS) e o aumento da atividade proteolítica da plasmina, uma vez que os leucócitos e as enzimas extracelulares bacterianas não são capazes de converter o plasminogênio em plasmina.…”