Element concentrations and stable oxygen and carbon isotope ratios of basalts from ODP Hole 148-896A

A number of independent observations, pointing to the influence of microbes, may be summarized as follows: (1) Alteration textures are reminiscent of microbes in terms of form and shape.

(2) Altered material contains appreciable amounts of C, N and K, and the N/C ratios are comparable to those of nitrogen-starved bacteria. (3) Samples stained with a dye (DAPI) that binds specifically to nucleic acids show the presence of DNA in the altered glass. Further, staining with fluorescent labeled oligonucleotide probes that hybridize specifically to 16S-ribosomal RNA of bacteria and archaea demonstrate their presence in the altered part of the glass.