The Magnetotactic Bacteria of the Churince Lagoon at Cuatro Cienegas Basin

Abstract

Magnetotactic bacteria (MTB) are prokaryotes whose movements are directed by the Earth’s geomagnetic field. The MTB are diverse in morphology, phylogeny, and physiology. They have unique cellular structures called magnetosomes, which are magnetic mineral crystals (iron) enveloped by a phospholipid bilayer membrane. These magnetosomes confer the ability of bacteria to have magnetotaxis. In this chapter, we will present some findings about the MTB inhabiting Churince Lagoon at Cuatro Cienegas Basin (CCB), such as Desulfovibrio magneticus, Magnetospirillum, Magnetospira, Magnetococcus, and Magnetovibrio. In a phylogenetic analysis, sequences of genes that encode the magnetosomes from CCB have similarities with those found in marine sediments with volcanic activity. These observations not only conform with other studies that have shown marine ancestry in microbes from CCB but also reaffirms the magmatic influences on the deep aquifer under the Sierra San Marcos and Pinos. Thus, water overexploitation for intensive agriculture in this oasis especially endangers the processes of the iron-sulfur cycle. This biogeochemical cycle is dependent on the deep aquifer and its sediments, which likely function as a depository of ancient anaerobic microbes such as the MTB.