TY - JOUR
T1 - Detection of hssS, hssR, hrtA, and hrtB genes and their expression by hemin in Staphylococcus epidermidis.
AU - Juárez-Verdayes, Marco A.
AU - González-Uribe, Pilar M.
AU - Peralta, Humberto
AU - Rodríguez-Martínez, Sandra
AU - Jan-Roblero, Janet
AU - Escamilla-Hernández, Rosalba
AU - Cancino-Diaz, Mario E.
AU - Cancino-Diaz, Juan C.
PY - 2012
Y1 - 2012
N2 - Staphylococcus aureus employs a heme sensing system (HssR-HssS) and a heme-regulated transporter efflux pump (HrtA-HrtB) to avoid the accumulation of heme, which is toxic at high concentrations. The detoxification system to heme has not been studied in Staphylococcus epidermidis . In this work, the hssR, hssS, hrtA, and hrtB genes were detected, and their expression when stimulated by hemin in S. epidermidis was explored. In silico genomic analyses exhibited that the genetic organization of the hssRS and hrtAB genes was identical in 11 Staphylococcus species analyzed, including S. epidermidis. Slight variations were found in their syntenic regions. The predicted secondary structure of HrtAB proteins from these species was almost identical to these of S. aureus. Additionally, hrtAB promoter sequences of some species were analyzed, and 1 or 2 different nucleotide substitutions were found in the downstream motif. Concentrations of hemin above 5 μmol/L inhibited S. epidermidis growth. However, S. epidermidis that was pre-exposed to a subinhibitory hemin concentration (1 μmol/L) was able to grow when inoculated into medium containing above 5 μmol/L hemin. The expression levels of hrtA and hrtB genes in S. epidermidis exhibited a significant difference when they were stimulated with hemin. Our results suggest that the HrtAB could be involved in hemin detoxification of S. epidermidis.
AB - Staphylococcus aureus employs a heme sensing system (HssR-HssS) and a heme-regulated transporter efflux pump (HrtA-HrtB) to avoid the accumulation of heme, which is toxic at high concentrations. The detoxification system to heme has not been studied in Staphylococcus epidermidis . In this work, the hssR, hssS, hrtA, and hrtB genes were detected, and their expression when stimulated by hemin in S. epidermidis was explored. In silico genomic analyses exhibited that the genetic organization of the hssRS and hrtAB genes was identical in 11 Staphylococcus species analyzed, including S. epidermidis. Slight variations were found in their syntenic regions. The predicted secondary structure of HrtAB proteins from these species was almost identical to these of S. aureus. Additionally, hrtAB promoter sequences of some species were analyzed, and 1 or 2 different nucleotide substitutions were found in the downstream motif. Concentrations of hemin above 5 μmol/L inhibited S. epidermidis growth. However, S. epidermidis that was pre-exposed to a subinhibitory hemin concentration (1 μmol/L) was able to grow when inoculated into medium containing above 5 μmol/L hemin. The expression levels of hrtA and hrtB genes in S. epidermidis exhibited a significant difference when they were stimulated with hemin. Our results suggest that the HrtAB could be involved in hemin detoxification of S. epidermidis.
UR - http://www.scopus.com/inward/record.url?scp=84875807416&partnerID=8YFLogxK
U2 - 10.1139/w2012-086
DO - 10.1139/w2012-086
M3 - Artículo
SN - 0008-4166
VL - 58
SP - 1063
EP - 1072
JO - Canadian Journal of Microbiology
JF - Canadian Journal of Microbiology
IS - 9
ER -