Viable Cell Detection with Fluorescent C-Sources
2461
AW539. The strain that did not take 2NBDG and
NBD-Gly was only 1 strain, E. coli ATCC 8739.
Therefore viable cells of 40 out of 41 strains could be
detected by only 2 ‰uorescent derivatives of glucose
and amino acid.
This method does not require long-time culture
and therefore is applicable to cells that grow slowly
or practically cannot be cultured. The incubation
time was as short as 1 min, so that total time can be
markedly shortened. These results imply a promising
property of our strategy focused on the ‰uorescent
derivatives of carbon sources. The next target is the
development of a 3rd ‰uorescent carbon source to
cover much more species and strains by combined
use.
Acknowledgment
This work was partly supported by a Grant-in
aid for Scientiˆc Research, Scientiˆc Research of
Priority Area: Single-cell Molecular Technology, the
Ministry of Education, Culture, Sports, Science, and
Technology. We thank Dr. Kodaka, Nissui Seiyaku
Co., Ltd., for his kind support in the selection and
the preparation of coliforms isolated from various
food samples. We thank Mr. Uehashi, GSI Creos
Corp., for his kind donation of various E. coli
strains.
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