TY  - JOUR
A1  - Makgotlho, Phuti E.
A1  - Marincola, Gabriella
A1  - Schäfer, Daniel
A1  - Liu, Quian
A1  - Bae, Taeok
A1  - Geiger, Tobias
A1  - Wasserman, Elizabeth
A1  - Wolz, Christine
A1  - Ziebuhr, Wilma
A1  - Sinha, Bhanu
T1  - SDS Interferes with SaeS Signaling of Staphylococcus aureus Independently of SaePQ
JF  - PLOS ONE
N2  - The Staphylococcus aureus regulatory saePQRS system controls the expression of numerous virulence factors, including extracellular adherence protein (Eap), which amongst others facilitates invasion of host cells. The saePQRS operon codes for 4 proteins: the histidine kinase SaeS, the response regulator SaeR, the lipoprotein SaeP and the transmembrane protein SaeQ. S. aureus strain Newman has a single amino acid substitution in the transmembrane domain of SaeS (L18P) which results in constitutive kinase activity. SDS was shown to be one of the signals interfering with SaeS activity leading to inhibition of the sae target gene eap in strains with SaeS(L) but causing activation in strains containing SaeS(P). Here, we analyzed the possible involvement of the SaeP protein and saePQ region in SDS-mediated sae/eap expression. We found that SaePQ is not needed for SDS-mediated SaeS signaling. Furthermore, we could show that SaeS activity is closely linked to the expression of Eap and the capacity to invade host cells in a number of clinical isolates. This suggests that SaeS activity might be directly modulated by structurally non-complex environmental signals, as SDS, which possibly altering its kinase/phosphatase activity.
KW  - host-cell invasion
KW  - 2-component system
KW  - strain Newman
KW  - allelic replacement
KW  - genome sequence
KW  - locus
KW  - gene
KW  - activation
KW  - expression
KW  - infection
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-128469
SN  - 1932-6203
VL  - 8
IS  - 8
ER  - 
TY  - JOUR
A1  - Wencker, Freya D. R
A1  - Marincola, Gabriella
A1  - Schoenfelder, Sonja M. K.
A1  - Maaß, Sandra
A1  - Becher, Dörte
A1  - Ziebuhr, Wilma
T1  - Another layer of complexity in Staphylococcus aureus methionine biosynthesis control: unusual RNase III-driven T-box riboswitch cleavage determines met operon mRNA stability and decay
JF  - Nucleic Acids Research
N2  - In Staphylococcus aureus, de novo methionine biosynthesis is regulated by a unique hierarchical pathway involving stringent-response controlled CodY repression in combination with a T-box riboswitch and RNA decay. The T-box riboswitch residing in the 5′ untranslated region (met leader RNA) of the S. aureus metICFE-mdh operon controls downstream gene transcription upon interaction with uncharged methionyl-tRNA. met leader and metICFE-mdh (m)RNAs undergo RNase-mediated degradation in a process whose molecular details are poorly understood. Here we determined the secondary structure of the met leader RNA and found the element to harbor, beyond other conserved T-box riboswitch structural features, a terminator helix which is target for RNase III endoribonucleolytic cleavage. As the terminator is a thermodynamically highly stable structure, it also forms posttranscriptionally in met leader/ metICFE-mdh read-through transcripts. Cleavage by RNase III releases the met leader from metICFE-mdh mRNA and initiates RNase J-mediated degradation of the mRNA from the 5′-end. Of note, metICFE-mdh mRNA stability varies over the length of the transcript with a longer lifespan towards the 3′-end. The obtained data suggest that coordinated RNA decay represents another checkpoint in a complex regulatory network that adjusts costly methionine biosynthesis to current metabolic requirements.
KW  - allelic replacement
KW  - expression
KW  - translation
KW  - mechanism
KW  - acid
KW  - endoribonuclease
KW  - antitermination
KW  - transcription
KW  - proteins
KW  - geometry
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259029
VL  - 49
IS  - 4
ER  -