from Astrobiology Website


Samples of a red rain that fell across the state of Kerala in India in July-August 2001 have been found to contain microscopic red cells (Louis and Kumar, 2006) of unknown origin. The early fall was associated with the 'thunder' and flash of a large meteor. They report that the cells appear to be very unusual in lacking a nucleus and DNA. Dr. Godfrey Louis kindly supplied us with a sample of this material for independent investigation in Cardiff.


High resolution electron microscopy has revealed internal structures as well as evidence of a replication cycle not commonly found in either bacteria or yeasts. These images are of thin cell slices viewed in the transmission electron microscope.

The first (above) shows three cells around 3 micrometers in diameter, with thick cell walls and a variety of nanostructures within a membrane, but with no identifiable nucleus. Apparent holes in the cell wall are real.

 

The cell on the right has larger holes and may have lost its cytoplasm.

The second picture shows a cell with shrunken membrane containing 'daughters' - two have well-defined cell walls while the third structure may be a further daughter in the process of development.


The latter picture (scale bar is 300 nanometers) shows the full resolution of that pictured in New Scientist magazine of 1st April 2006 (No. 2545, p.12; www.newscientist.com) with the caption "Does it look alien to you?". New Scientist letters have also carried various suggestions for known terrestrial micro-organisms - these pictures should stimulate further ideas!


Further work in progress has yielded positive for DNA using DAPI staining in the cells and daughters. However, this identification is not yet fully confirmed, and might be considered equivocal. We hope to pursue our efforts in extracting DNA (if it exists), amplifying it and carrying out genetic sequencing, but his work takes time.
 


References

Persons associated with this work

  • Cardiff University: N.C. Wickramasinghe, N. Miyake, S.Al-Mufti, M.K.Wallis (CCAB), A.C. Hann (Biosci. EM Lab), D. Lloyd, S.K. Sheppard (Microbiology group)

  • Mahatma Gandhi University, Kerala. India: G. Louis and S. Kumar