Activity of Iron-uptake System of Staphy lococcus aureus According to the Isolation Sites

Shin, Sung Heui; Lim, Yong; Kim, Jin Ho

Abstract

OBJECTIVE
We tried to investigate the activity of iron-uptake system (IUS) of Stap hylococcus aureus according to the isolation sites and thus the relatedness between IUS and virulence.
METHODS
Seventy clinical isolates were classified into the isolates from patients (56), from doctors and nurses (7) and from hospital environments (7). The isolates from patients (56) were sub-classified into the isolates from hospitalized patients (40; HP) and from outpatients (16; OP). Siderophore activity was measured CAS agar diffusion assay and transferrin-binding protein (tbp) was detected by receptor-ligand binding assay.
RESULTS
There was no difference of siderophore production among the isolates from patients, doctors and nurses, and hospital environments (P>0.05). However, the isolates from patients expressed more tbp than the isolates from doctors and nurses and hospital environments (P<0.05). The isolates from OP produced more siderophore and expressed more tbp than the isolates from HP (P<0.05).
CONCLUSION
These results suggested that Staphylococcus aureus with more active IUS is more virulent and more easily causes infection even in patients with relatively good general condition.