To investigate the microbial biodiversity of the air of specific
environments, and to upgrade Fourier-transform infrared
(FTIR) spectral libraries with the spectra of bacterial isolates
from such habitats, air samples were collected from different
locations of medical practices and pharmaceutical clean
rooms in Germany (G. Rieser, S. von Brehmer, G.
Schuffenhauer, S. Scherer & M. Wenning, unpublished).
Cells were incubated on tryptone soy agar (TSA) at 30 uC for
24 h. FTIR samples were then prepared and spectra acquired
as described by Oberreuter et al. (2002), using a Tensor 27
FTIR spectrometer (Bruker Optics) coupled to a HTS-XT
high-throughput device (Bruker Optics). Prior to identification,
spectra were pre-processed according to Oberreuter
et al. (2002). Identification was performed using the OPUS
5.5 software package (Bruker), in combination with libraries
of reference spectra. Isolates that displayed FTIR spectra that
did not match any reference in the libraries were identified
by gene sequence analysis before the corresponding spectra
were integrated into the system. During the course of this
study, three novel strains, designated strains WS4599,
WS4601T and WS4602, were identified as being members
of the genus Micrococcus. Strains WS4601T and WS4602
were isolated from the examination room and cloakroom
of a single medical practice, respectively, whereas strain
WS4599 was isolated from a pharmaceutical clean room