Nannobacteria, Organic Matter, and Precipitation in Hot Springs, Viterbo, Italy: Distinctions and Relevance

Abstract

Abstract Tiny (50-200 nm) spheroids were first discovered by Folk through SEM work on the hot springs of Viterbo Italy. He termed these small, spherical structures “nannobacteria,” and proposed that they may be important agents in precipitation of CaCO3, as needle-like crystals of the mineral aragonite, and as bundles of such needle-like crystals (termed “fuzzy dumbbells”), or as elongated crystals of the mineral calcite. During the past 15 years, nanometer-scale spheroids have been discovered in the geological, medical, and astronomical worlds. There can be no doubt as to their existence, but their significance and origin remain a subject of continuing controversy. Even the spelling (“nanno-“), which has been the standard in biology, geology, and paleontology going back to the 19th century, has been questioned. Whether or not they are truly bacteria or any form of life has been a subject of heated debate.