title: Temperate Streptococcus thermophilus phages expressing superinfection exclusion proteins of the Ltp type.
abstract: Lipoprotein Ltp encoded by temperate Streptococcus thermophilus phage TP-J34 is the prototype of the wide-spread family of host cell surface-exposed lipoproteins involved in superinfection exclusion (sie). When screening for other S. thermophilus phages expressing this type of lipoprotein, three temperate phages-TP-EW, TP-DSM20617, and TP-778-were isolated. In this communication we present the total nucleotide sequences of TP-J34 and TP-778L. For TP-EW, a phage almost identical to TP-J34, besides the ltp gene only the two regions of deviation from TP-J34 DNA were analyzed: the gene encoding the tail protein causing an assembly defect in TP-J34 and the gene encoding the lysin, which in TP-EW contains an intron. For TP-DSM20617 only the sequence of the lysogeny module containing the ltp gene was determined. The region showed high homology to the same region of TP-778. For TP-778 we could show that absence of the attR region resulted in aberrant excision of phage DNA. The amino acid sequence of mature LtpTP-EW was shown to be identical to that of mature LtpTP-J34, whereas the amino acid sequence of mature LtpTP-778 was shown to differ from mature LtpTP-J34 in eight amino acid positions. LtpTP-DSM20617 was shown to differ from LtpTP-778 in just one amino acid position. In contrast to LtpTP-J34, LtpTP-778 did not affect infection of lactococcal phage P008 instead increased activity against phage P001 was noticed.
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany ; Medical Biology Department, Faculty of Medicine, Jazan University Jazan, Kingdom of Saudi Arabia ; Department of Biotechnology, Agricultural Research Center, Animal Health Research Institute Cairo, Egypt.
authors.forename: Yahya
authors.initials: Y
authors.lastname: Ali
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Koberg
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Heßner
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Xingmin
authors.initials: X
authors.lastname: Sun
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Rabe
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Angela
authors.initials: A
authors.lastname: Back
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Horst
authors.initials: H
authors.lastname: Neve
authors.affiliation: Department of Microbiology and Biotechnology, Max Rubner-Institut (Federal Research Institute of Nutrition and Food) Kiel, Germany.
authors.forename: Knut J
authors.initials: KJ
authors.lastname: Heller
keywords: Streptococcus thermophilus; TP-778L; TP-DSM20617; TP-EW; TP-J34; prophage; superinfection exclusion