Original features of cell-envelope proteinases of Lactobacillus helveticus. A review

► The review focused on L. helveticus proteinases regarding genes, CEP activities and strain diversity. ► L. helveticus seems to be unique in terms of variability in number of CEP genes. ► prtH2 gene is present for the 29 analyzed strains and 18/29 also exhibited prtH gene. ► Few data are about regulation of proteinase biosynthesis or peptide transport. ► When both proteinases are present, hydrolysis of αs1-casein in enhanced.