Summary of the second-half of CUBE ChatShaala: 11th February 2021
A gripping discussion on the three-time Nobel Prize winning soil nematode Caenorhabditis elegans took place! @magpie (re)introduced us to her CUBE Nematode HomeLab in Kolkata, WB where she took an initiative to isolate nematodes (transparent wriggling creatures ~1mm in length) from the soil.
Barring the conventional method of using 2% Agar medium as a surface for the nematodes, raw potato was used. Moist soil (source of soil nematodes) was placed in the periphery that was followed by addition of a few drops of milk (instead of E. coli OP50) as the source of nutrients and bacteria.
Starting this setup in early-December 2020, first signs of nematode-like creatures were seen six days post preparation of the setup.
This was the start of a mixed culture of nematodes!
With the help of a microscope available at @magpie’s place, photos of the nematodes were captured and they were used for identification of the nematodes.
(Note: Visualising organisms as small as 1mm isn’t difficult if we use the digital zooming of our phone camera alongwith a stable hand to capture their movement!
From the identification part, @magpie suspects these soil nematodes to be of the Rhabditidae family (Why? References need to be quoted).
The interesting part of the discussion was that there are different morphological features of nematodes of the same species differing in gender.
For example, the nematode that is hermaphrodite (possessing both female and male sex organs) has tapering (narrow) ends (posterior) whereas the male doesn’t.
Apart from this, the (utmost important) part that I found confusing initially was the positioning of vulva and pharyngeal bulbs. When we talk of C. elegans, its counterpart (another commonly found soil nematode) Oscheius tipulae doesn’t go without having a mention.
Thanks to this reference shared by @Arunan, we were able to see the thin line that separates both these soil nematodes.
The above reference has a micrograph as well as a schematic diagram that clearly shows the presence of two pharyngeal bulbs (at the anterior end) in C. elegans but just a single pharyngeal bulb in O. tipulae!
According to @magpie, after identifying the nematodes that have been isolated from the soil, the needle points towards Rhabditidae family but now that we have a reference (pointing totally opposite to the claim), we sustain a chance to disprove what was thought to be correct earlier!
Also, there are cultures that are suspected to be single line cultures (SLCs) of nematodes (more clarification needed on this!). All of this has been done in just a span of two months that too at home! Well, who might have thought that attempting to isolate an extensively studied model organism would be as frugal as this!!?
Mary Ann Felix, famous and familiar to Cubists has been in Mumbai at Koushika Lab TIFR, Mumbai, if inspiration is required for Cubists to go ahead on their hunt for C elegans in India.