Cell (filamentous shaped) dimensions during exponential growth at 3°C

Range diameter average 0.45±0.067 (range 0.38-0.64): length average 8.57±4 (range 3.04-16) µm
Organism Bacteria Shewanella oneidensis MR-1
Reference Abboud R et al., Low-temperature growth of Shewanella oneidensis MR-1. Appl Environ Microbiol. 2005 Feb71(2):811-6. DOI: 10.1128/AEM.71.2.811-816.2005 p.812 right column 2nd paragraphPubMed ID15691935
Method P.811 right column 3rd paragraph: "For epifluorescent microscopy observations, cells were stained for 5 min with acridine orange (50 μl of 0.1% [wt/vol] acridine orange in 2 ml of a 1:100 dilution of the cell culture) and filtered on a Nuclepore polycarbonate membrane (0.2 μm pore size) (Osmonics Inc.). For electron microscopy of whole-cell suspensions, cells were fixed for 30 min with the paraformaldehyde-glutaraldehyde Karnovsky fixative in sodium cacodylate buffer (0.2 M, pH 7.4). After fixation the cells were rinsed with cacodylate buffer and washed with phosphate-buffered saline buffer (pH 7.4). One hundred microliters of the fixed cells were placed on Formvar carbon grids (Ted Pella Inc.) and stained for 30 s with 1% uranyl acetate. The samples were observed with a Jeol 100 CX II transmission electron microscope."
Comments P.812 right column 2nd paragraph: "During exponential growth at 3°C and 22°C, the relationships between optical density and both biomass (dry weight) and protein content were linear (not shown). Cells of MR-1 grown at 22°C were rods measuring between 0.4 and 0.9 μm (average, 0.61 ± 0.11 μm) in diameter and 1.2 to 9.6 μm (average, 3.38 ± 1.7 μm) in length (measured from transmission electron microscope images), whereas cells growing at 3°C were filamentous, measuring between 0.38 and 0.64 μm (average, 0.45 ± 0.067 μm) in diameter and between 3.04 and 16 μm (average, 8.57 ± 4 μm) in length (Fig. ​(Fig.1).1). These averages are significantly different based on a Student t test for unequal variances and α = 0.01. The transmission electron microscope results underestimated the length of the 3°C-grown filaments because many filaments exceeded in length the dimensions of the transmission electron microscope pictures. Under optical microscopy, some filamentous cells were much longer (exceeding 70 μm). These filamentous cells were motile, and some aggregated into groups of up to 10 to 20 entangled filaments."
Entered by Uri M
ID 112813