Regulatory systems agr and sar in Staphylococcus Aureus

Staphylococcus aureus is an opportunistic pathogen causing many serious human and animal diseases . Infection is associated with the expression of virulence factors , mainly controlled by two regulatory systems agr and sar . Agr locus consists of two transcripts : RNAIII that is RNAII and the regulatory molecule encoding four proteins required for the stimulation of transcription of RNAII and RNAIII . Sar locus encoding a protein SarA and agr activator which binds to DNA is composed of three overlapping reading frames .

Antimicrobial peptides-structure and function

The defense system of plants and animals includes , inter alia, peptides with antimicrobial or antifungal properties . Despite the large variation in terms of occurrence and sequence of amino acids, most of them are cationic amphipathic molecules with structure . Due to the spatial structure can be distinguished among them several main groups: 1 Linear , forming a- helices ; 2 Antiparallel b sheets stabilized intramolecular disulfide bonds ; 3 A + b structure stabilized by disulfide bridges ; 4 Cyclic structures ; 5 Linear sequence enriched in certain amino acids .

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Andrzej Łukaszyk - przewodniczący, Zofia Bielańska-Osuchowska, Szczepan Biliński, Mieczysław Chorąży, Aleksander Koj, Włodzimierz Korochoda, Leszek Kuźnicki, Aleksandra Stojałowska, Lech Wojtczak

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