Ultrastructure of the Pathogenic Bacteria Mobiluncus mulieris

Abstract

Mobiluncus spp. are gram variable anaerobic rods found associated with bacterial vaginosis. Recent molecular analyses of Falcivibrio spp. has identified these species as misclassified Mobiluncus [1]. We therefore will use Mobiluncus for further description of these organisms.Clinical isolates of M. mulieris (ATCC) were maintained on Columbia CNA Blood Agar under anaerobic conditions [2]. For growth of cultures for electron microscopic analyses, cells were grown anaerobically in thioglycolate broth for 24 hr at 37 o C, collected by centrifugation and transferred immediately to 4% paraformaldehyde, 2.5% glutaraldehyde in either sodium cacodylate or Sorenson's phosphate buffer. Cells were fixed for 24 hr, rinsed in appropriate buffer, and post-fixed in 1% OsO 4. The cells were dehydrated in an ascending ethanol series and transferred to propylene oxide as a transition fluid. The cells were then infiltrated in Epon-Araldite (substituted; Electron Microscopy Sciences) and embedded in BEEM capsules. The resin was cured 24 hr at 60 o C, semithick sections were obtained (Leica Ultracut UCT) for light microscopic analysis. Thin sections were obtained using a Diatome diamond knife, picked up on copper grids, stained in uranyl acetate and a modified Sato's lead stain [3]. Sections were imaged with a Philips CM100 and digital images collected (SIA-7C CCD camera; Scientific Instruments and Applications, Inc.; Duluth GA).

Have flagella a preferred orientation during early stages of biofilm formation?: AFM study using patterned substrates

“…Flagella have been traditionally observed by means of fluorescence microscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM) with different invasive treatments [25] such as fixation with glutaralaldehyde, and single-and multi-colour fluorescent labelling [11,26]. In the last few years, atomic force microscopy (AFM) has also been used to study the early stages of biofilm formation [27][28][29][30] providing 3-D images at nanoscale resolution and minimal or no sample preparation.…”