Lyophilized Escherichia coli strains stored for 40–50 years: morphological, serotypic, biochemical characteristics and drug sensitivity. - Ermenlieva, Neli; Georgieva, Emilia; Tsankova, Gabriela; Nedelcheva, Gergana; Laleva, Krasimira; Stamova, Sylvia; Kostadinova, Todorka (Biotechnology & Biotechnological Equipment, 2023)