Attachment Behavior of Leaching Bacteria to Metal Sulfides Elucidated by Combined Atomic Force and Epifluorescence Microscopy

2009 ◽  
Vol 71-73 ◽  
pp. 337-340 ◽  
Author(s):  
Bianca M. Florian ◽  
Nanni Noël ◽  
Soeren Bellenberg ◽  
J. Huergo ◽  
Thore Rohwerder ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Extracellular Polymeric Substances ◽  
Spatial Arrangement ◽  
Epifluorescence Microscopy ◽  
Metal Sulfides ◽  
Mineral Surface ◽  
Planktonic Cells ◽  
Force Microscopy ◽  
Atomic Force ◽  
Leaching Bacteria

The aim of the study was to quantify and to visualize colonization of metal sulfides by pure and mixed cultures. Strains of the genera Acidithiobacillus and Leptospirillum were tested. Sessile and planktonic cells were visualized by fluorescence microscopy using 4',6-diamidino-2-phenylindole (DAPI) and FISH. Additionally, atomic force microscopy was used for the investigations on cell morphology, spatial arrangement of cells on metal sulfides and mineral surface topography. It was shown that the morphology of sessile cells was totally different as compared with planktonic ones. Interactions of different species resulted in increased production of extracellular polymeric substances (EPS) or caused negligible-attaching bacteria to be incorporated into a biofilm by the good attaching ones. Consequently, biofilm formation was furthered.

scholarly journals Novel Combination of Atomic Force Microscopy and Epifluorescence Microscopy for Visualization of Leaching Bacteria on Pyrite

2007 ◽  
Vol 74 (2) ◽  
pp. 410-415 ◽  
Author(s):  
Stefanie Mangold ◽  
Kerstin Harneit ◽  
Thore Rohwerder ◽  
Günter Claus ◽  
Wolfgang Sand
Keyword(s):  
Atomic Force Microscopy ◽  
Extracellular Polymeric Substances ◽  
Metal Sulfide ◽  
Epifluorescence Microscopy ◽  
Bacterial Cells ◽  
Cell Integrity ◽  
Force Microscopy ◽  
Topographic Features ◽  
Atomic Force ◽  
Leaching Bacteria

ABSTRACT Bioleaching of metal sulfides is an interfacial process comprising the interactions of attached bacterial cells and bacterial extracellular polymeric substances with the surface of a mineral sulfide. Such processes and the associated biofilms can be investigated at high spatial resolution using atomic force microscopy (AFM). Therefore, we visualized biofilms of the meso-acidophilic leaching bacterium Acidithiobacillus ferrooxidans strain A2 on the metal sulfide pyrite with a newly developed combination of AFM with epifluorescence microscopy (EFM). This novel system allowed the imaging of the same sample location with both instruments. The pyrite sample, as fixed on a shuttle stage, was transferred between AFM and EFM devices. By staining the bacterial DNA with a specific fluorescence dye, bacterial cells were labeled and could easily be distinguished from other topographic features occurring in the AFM image. AFM scanning in liquid caused deformation and detachment of cells, but scanning in air had no effect on cell integrity. In summary, we successfully demonstrate that the new microscopic system was applicable for visualizing bioleaching samples. Moreover, the combination of AFM and EFM in general seems to be a powerful tool for investigations of biofilms on opaque materials and will help to advance our knowledge of biological interfacial processes. In principle, the shuttle stage can be transferred to additional instruments, and combinations of AFM and EFM with other surface-analyzing devices can be proposed.

Biofilm Formation and Extracellular Polymeric Substances (EPS) Analysis by New Isolates of Leptospirillum, Acidithiobacillus and Sulfobacillus from Armenia

2015 ◽  
Vol 1130 ◽  
pp. 153-156 ◽  
Author(s):  
Arevik K. Vardanyan ◽  
Narine S. Vardanyan ◽  
Levon Markosyan ◽  
Wolfgang Sand ◽  
Mario Vera ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Biofilm Formation ◽  
Extracellular Polymeric Substances ◽  
Epifluorescence Microscopy ◽  
Sulfide Ores ◽  
Uronic Acids ◽  
Force Microscopy ◽  
Atomic Force

Biofilm formation by new isolates, Leptospirillum sp. strain ZC, Acidithiobacillus sp. strain 61 and Sulfobacillus sp. strain 6 isolated from different biotopes of sulfide ores in Armenia on pyrite was studied by atomic force microscopy (AFM) combined with epifluorescence microscopy (EFM). It was revealed that all the tested species formed monolayer biofilms The results showed that in contrast to Acidithiobacillus sp. strain 61 and Sulfobacillus sp. strain 6, cells of Leptospirillum sp. strain ZC were often observed by clusters and aggregates.The composition of capsular and colloidal EPS formed by isolated Leptospirillum sp. strain ZC, Acidithiobacillus sp. strain 61 and Sulfobacillus sp. strain 6 was studied. It was revealed that the EPS of all three species grown on iron (II) mainly consisted of carbohydrates, proteins as well as uronic acids.

Combined Atomic Force and Fluorescence Microscopy of Biofilms formed by Leaching Bacteria on Opaque Substrata

2007 ◽  
Vol 20-21 ◽  
pp. 371-374
Author(s):  
Stefanie Mangold ◽  
Kerstin Harneit ◽  
Wolfgang Sand
Keyword(s):  
Biofilm Formation ◽  
Epifluorescence Microscopy ◽  
Contact Mode ◽  
Atomic Force ◽  
Afm Probe ◽  
Leaching Bacteria ◽  
Mineral Sulfides ◽  
Spring Constants ◽  
Imaging Conditions ◽  
Fluid Imaging

Leaching bacteria attach to their substrates, i.e. mineral sulfides, and form monolayered biofilms. In this study the biofilm formation of Acidithiobacillus ferrooxidans A2 on pyrite was examined using atomic force and epifluorescence microscopy (AFM and EFM, respectively). A novel system by JPK instruments, the BioMaterial WorkstationTM, allows the investigation of the same location on an opaque sample with AFM and EFM. Until recently this was only possible for translucent samples. Sessile bacteria on pyrite coupons were stained with 4’,6-diamidino-2- phenylindol (DAPI) and visualized by EFM as well as AFM. The best imaging conditions for AFM were assessed. Scans of bacteria attached to pyrite were performed in contact mode in air as well as in tapping mode in fluid. Imaging in fluid was more challenging than imaging in air as bacteria tend to detach from their substratum. To avoid the dislocation of microorganisms by the AFM probe the sample was dried in air for 1 h prior to scanning in fluid. Scanning in air was performed with the whole range of cantilever spring constants tested (k = 0.03 N/m to k = 0.65 N/m) while, for scanning in fluid, best results were achieved using stiffer cantilevers (k = 0.65 N/m).

scholarly journals Atomic force microscopy of a ctpA mutant in Rhizobium leguminosarum reveals surface defects linking CtpA function to biofilm formation

Microbiology ◽  
2011 ◽  
Vol 157 (11) ◽  
pp. 3049-3058 ◽  
Author(s):  
Jun Dong ◽  
Karla S. L. Signo ◽  
Elizabeth M. Vanderlinde ◽  
Christopher K. Yost ◽  
Tanya E. S. Dahms
Keyword(s):  
Atomic Force Microscopy ◽  
Mutant Strain ◽  
Biofilm Formation ◽  
Rhizobium Leguminosarum ◽  
Surface Defects ◽  
Ion Concentration ◽  
Adhesive Properties ◽  
Surface Ultrastructure ◽  
Force Microscopy ◽  
Atomic Force

Atomic force microscopy was used to investigate the surface ultrastructure, adhesive properties and biofilm formation of Rhizobium leguminosarum and a ctpA mutant strain. The surface ultrastructure of wild-type R. leguminosarum consists of tightly packed surface subunits, whereas the ctpA mutant has much larger subunits with loose lateral packing. The ctpA mutant strain is not capable of developing fully mature biofilms, consistent with its altered surface ultrastructure, greater roughness and stronger adhesion to hydrophilic surfaces. For both strains, surface roughness and adhesive forces increased as a function of calcium ion concentration, and for each, biofilms were thicker at higher calcium concentrations.

The Influence of the Marine Bacterium Vibrio Natriegens Growth on Metallic Corrosion as Studied by Microscope Technologies

2008 ◽  
Vol 47-50 ◽  
pp. 169-172
Author(s):  
Yan Sheng Yin ◽  
Sha Cheng ◽  
Kin Tak Lau ◽  
Shou Gang Chen ◽  
Tao Liu
Keyword(s):  
Biofilm Formation ◽  
Marine Bacterium ◽  
Cluster Formation ◽  
Metallic Surfaces ◽  
Distance Curve ◽  
Force Microscopy ◽  
Atomic Force ◽  
Metallic Corrosion ◽  
Scanning Electron ◽  
Proliferation Period

Biofilm formation and the adsorption of nonsulfate-reducing marine bacterium Vibrio natriegens (V. natriegen) to different metallic surfaces have been studied by atomic force microscopy (AFM). The nature of extracellular polymeric substance (EPS) has been monitored through the force-distance curve. EPS may act as adhesive binding adjacent cells and thus further enhance the aggregation of microbes during cluster formation due to its adhesiveness in nature. The AFM images supply the change of the morphology of microbial cells and colonies, the distribution of microbial colonies and the presence of EPS on the surfaces with immersion. Results show that the biofilms formed on the surfaces increase in thickness and heterogeneity with time and that 3~7 days is the proliferation period of the bacteria on metallic surfaces. The corrosion type of the metals by V. natriegens could be confirmed as typical pitting attack through scanning electron microscopy (SEM) observation.

scholarly journals Comparative Analysis of Attachment to Chalcopyrite of Three Mesophilic Iron and/or Sulfur-Oxidizing Acidophiles

Minerals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 406 ◽  
Author(s):  
Qian Li ◽  
Baojun Yang ◽  
Jianyu Zhu ◽  
Hao Jiang ◽  
Jiaokun Li ◽  
...  
Keyword(s):  
Adhesion Force ◽  
Bacterial Attachment ◽  
Copper Recovery ◽  
Metal Sulfides ◽  
Acidithiobacillus Thiooxidans ◽  
Adhesion Forces ◽  
Force Microscopy ◽  
Atomic Force ◽  
Initial Adhesion ◽  
Sulfur Oxidizing

Adhesion plays an important role in bacterial dissolution of metal sulfides, since the attached cells initiate the dissolution. In addition, biofilms, forming after bacterial attachment, enhance the dissolution. In this study, interactions between initial adhesion force, attachment behavior and copper recovery were comparatively analyzed for Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferrooxidans during bioleaching of chalcopyrite. The adhesion forces between bacteria and minerals were measured by atomic force microscopy (AFM). L. ferrooxidans had the largest adhesion force and attached best to chalcopyrite, while A. ferrooxidans exhibited the highest bioleaching of chalcopyrite. The results suggest that the biofilm formation, rather than the initial adhesion, is positively correlated with bioleaching efficiency.

Sign in / Sign up

Export Citation Format

Share Document