Origin Localization in three Gram Positive Bacteria - veeninglab/BactMAP GitHub Wiki

Download dataset

Download a .zip of this collection here

Do the tutorial

You can use this dataset to recreate figure 4 of our preprint (coming soon). Find the tutorial here

General Organization

This dataset is made up of three image analysis subsets:

  1. Bacillus subtilis with tetR-mCherry/oriC::tetO
  2. Streptococcus pneumoniae with parB(p)-m(sf)GFP/oriC-parS
  3. Staphylococcus aureus with parB-m(sf)GFP

All three sets contain fluorescence microscopy images of these strains (saved as 8-bit .TIFFs) as the files generated by phase-contrast segmentation & spot detection. To save disk space, only the fluorescence channel image stack is included in the dataset. If you would like to use the phase-contrast images as well, please contact me directly.

Growth conditions & Microscopy settings

The growth conditions & microscopy settings are described in our preprint.

Segmentation & Spot detection

For all three subsets, ISBatch’s Single Molecule BioPhysics FIJI plugin was used to detect fluorescent spots. For this, the “peakfitter” option in the plugin was used to detect single spots in each image.For the detection of cells, three different segmentation programs were used:

The Bacillus subtilis cells were segmented using ObjectJ and ChainTracer. For this, phase contrast images where used to detect the cells & far-red images with MitoTracker Far Red staining were used to detect the septa. After this, wrongly detected septa and non-detected septa were corrected using the ChainTracer interactive interface. Using the setting file object_settings.ojj (included in dataset), the bounding box coordinates of the bacilli were saved in a tab-delimited .txt-file (bsubtilis_box.txt, included in dataset).

The Streptococcus pneumoniae cells were segmented using Morphometrics. The settings used were saved as Morphometrics_prefs.MAT (included in dataset). The output containing the cell contours (MK387_phase_18-Apr-2019_CONTOURS.MAT) was saved.

The Staphylococcus aureus cells were segmented using SuperSegger. The best existing constants were tested and 60xBay was used to do the segmentation based on phase-contrast. After segmentation, the septa were assessed manually and corrected for when necessary.

Overview of files:

Files in the Bacillus subtilis-dataset:

File Type Description
bacillus_RFP 8-bit TIF RFP (mCherry) channel image stack
bsubtilis_box tab-delimited txt output of ChainTracer (objectJ) analysis containing the coordinates of the minimal bounding box of each cell
ChainTracer03k objectJ-file (.ojj) settings file used to run ChainTracer in imageJ
objectJ_settings objectJ-file (.ojj) settings file used to save the whole bounding-box
RRB01_peakfitter_RFP CSV output of ISBatch’s PeakFitter option with fluorescent peak coordinates

Files in the Streptococcus pneumoniae-dataset:

File Type Description
MK387_GFP 8-bit TIF Image stack of GFP-channel (oriC-GFP)
MK387_phase_18-Apr-2019_CONTOURS .MAT (matlab file) Output of morphometrics containing cell contours
Morphometrics_prefs .MAT (matlab file) Morphometrics parameters used
peakfitter_GFP CSV output of ISBatch’s PeakFitter option with fluorescent peak coordinates

Files in the Staphylococcus aureaus-dataset:

File/Folder Type Description
raw_im Folder containing TIFs separate TIF images as used by SuperSegger for segmentation
xy0 to xy6 Folder containing matlab files “cellxxx” and “clist” Cell file: cell information & mask for each cell, listed per image frame (xy). Clist: summary of cell information of one image frame (xy) in one file.
CONST .MAT (matlab file) the parameter set used for segmentation
peakfitter_GFP tab-delimited txt output of ISBatch’s PeakFitter option with fluorescent peak coordinates
Stack_parB_GFP 8-bit TIF stack image stack with GFP channel (parB-GFP)