Document Detail


Determination of the biomasses of small bacteria at low concentrations in a mixture of species with forward light scatter measurements by flow cytometry
MedLine Citation:
PMID:  9758817     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
The forward light scatter intensity of bacteria analyzed by flow cytometry varied with their dry mass, in accordance with theory. A standard curve was formulated with Rayleigh-Gans theory to accommodate cell shape and alignment. It was calibrated with an extinction-culture isolate of the small marine organism Cycloclasticus oligotrophus, for which dry weight was determined by CHN analysis and 14C-acetate incorporation. Increased light scatter intensity due to formaldehyde accumulation in preserved cells was included in the standard curve. When differences in the refractive indices of culture media and interspecies differences in the effects of preservation were taken into account, there was agreement between cell mass obtained by flow cytometry for various bacterial species and cell mass computed from Coulter Counter volume and buoyant density. This agreement validated the standard curve and supported the assumption that cells were aligned in the flow stream. Several subpopulations were resolved in a mixture of three species analyzed according to forward light scatter and DNA-bound DAPI (4', 6-diamidino-2-phenylindole) fluorescence intensity. The total biomass of the mixture was 340 &mgr;g/liter. The lowest value for mean dry mass, 0.027 +/- 0.008 pg/cell, was for the subpopulation of C. oligotrophus containing cells with a single chromosome. Calculations from measurements of dry mass, Coulter Counter volume, and buoyant density revealed that the dry weight of the isolate was 14 to 18% of its wet weight, compared to 30% for Escherichia coli. The method is suitable for cells with 0.005 to about 1.2 pg of dry weight at concentrations of as low as 10(3) cells/ml and offers a unique capability for determining biomass distributions in mixed bacterial populations.
Authors:
Robertson; Button; Koch
Related Documents :
17227597 - Cell function in the bovine mammary gland: a preliminary study on interdependence of he...
19326757 - Cell density of the lamina propria of neonatal vocal folds.
9764627 - Factors associated with maternal cell contamination in amniocentesis samples as evaluat...
1192607 - An automated, direct method for measuring adipocyte cell size.
19439217 - The use of ebselen for radioprotection in cultured cells and mice.
3161437 - Measurements of cell-mediated cytotoxicity on target cells labelled with the indium-111...
Publication Detail:
Type:  JOURNAL ARTICLE    
Journal Detail:
Title:  Applied and environmental microbiology     Volume:  64     ISSN:  1098-5336     ISO Abbreviation:  Appl. Environ. Microbiol.     Publication Date:  1998 Oct 
Date Detail:
Created Date:  1998-10-08     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  7605801     Medline TA:  Appl Environ Microbiol     Country:  -    
Other Details:
Languages:  Eng     Pagination:  3900-9     Citation Subset:  -    
Affiliation:
Institute of Marine Science, University of Alaska Fairbanks, Fairbanks, Alaska 99775, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Effects of visible light and UV radiation on photosynthesis in a population of a hot spring cyanobac...
Next Document:  The introduction into bacillus sphaericus of the Bacillus thuringiensis subsp. medellin Cyt1Ab1 gene...