One of the advantages for initial survival of inhaled fungal
spores in the respiratory tract is the ability for iron acquisition
via hemolytic factor-production. To examine the ability
of indoor Aspergillus and Penicillium affecting hemolysis,
the secreted factors during the growth of thirteen strains from
eight species were characterized in vitro for their hemolytic
activity (HA) and CAMP-like reaction. The hemolytic index
of HA on human blood agar of Aspergillus micronesiensis,
Aspergillus wentii, Aspergillus westerdijkiae, Penicillium citrinum,
Penicillium copticola, Penicillium paxilli, Penicillium
steckii, and Penicillium sumatrense were 1.72 ± 0.34, 1.61 ±
0.41, 1.69 ± 0.16, 1.58 ± 0.46, 3.10 ± 0.51, 1.22 ± 0.19, 2.55 ±
0.22, and 1.90 ± 0.14, respectively. The secreted factors of
an Aspergillus wentii showed high HA when grown in undernourished
broth at 25°C at an exponential phase and were
heat sensitive. Its secreted proteins have an estimated relative
molecular weight over 50 kDa. Whereas, the factors of
Penicillium steckii were secreted in a similar condition at a
late exponential phase but showed low HA and heat tolerance.
In a CAMP-like test with sheep blood, the synergistic hemolytic
reactions between most tested mold strains and Staphylococcus
aureus were identified. Moreover, the enhancement
of α-hemolysis of Staphylococcus aureus could occur through
the interaction of Staphylococcus aureus-sphingomyelinase
and CAMP-like factors secreted from Aspergillus micronesiensis.
Further studies on the characterization of purified hemolytic-
and CAMP-like-factors secreted from Aspergillus
wentii and Aspergillus micronesiensis may lead to more understanding
of their involvement of hemolysis