title: Proline iminopeptidase PepI overexpressing Lactobacillus casei as an adjunct starter in Edam cheese.
abstract: In this study the growth of genetically modified Lactobacillus casei LAB6, overexpressing proline iminopeptidase PepI and its capacity to increase free proline was investigated during ripening of Edam cheese. The strain successfully survived 12 weeks of ripening period in cheese. The food-grade plasmid pLEB604, carrying the pepI gene, was stable, and PepI enzyme was active in LAB6 cells isolated at different stages of the ripening process. However, HPLC analyses indicated that Lb. casei LAB6 could not increase the amount of free proline in ripened cheese.
authors.affiliation: Department of Food and Environmental Sciences; University of Helsinki; Helsinki, Finland.
authors.forename: Sahar
authors.initials: S
authors.lastname: Navidghasemizad
authors.affiliation: Department of Food and Environmental Sciences; University of Helsinki; Helsinki, Finland.
authors.forename: Timo M
authors.initials: TM
authors.lastname: Takala
authors.affiliation: Department of Food and Environmental Sciences; University of Helsinki; Helsinki, Finland.
authors.forename: Tapani
authors.initials: T
authors.lastname: Alatossava
authors.affiliation: Department of Food and Environmental Sciences; University of Helsinki; Helsinki, Finland.
authors.forename: Per Ej
authors.initials: PE
authors.lastname: Saris
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000626:Aminopeptidases / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002611:Cheese / Q000382:microbiology*; D005511:Food Handling; D005516:Food Microbiology; D007780:Lacticaseibacillus casei / Q000201:enzymology* / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D013649:Taste
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D000626:Aminopeptidases; C022450:prolyl aminopeptidase
keywords: Edam cheese; PepI; bitterness; proline