Sphingolipids in Bacteria and Fungi

Sphingolipids constitute a distinctive group of membrane lipids characterized by a long-chain (monounsaturated), di-hydroxy amine structure (sphingosine). Sphingolipids are essential components of the plasma membrane of mammalian cells where they are typically found in the outer leaflet. They are also membrane constituents of some bacterial groups, particularly anaerobes. These groups include Bacteroides, Prevotella, Porphyromonas, Fusobacterium, Sphingomonas, Sphingobacterium, Bdellovibrio, Cystobacter, Mycoplasma, Flectobacillus, and possibly Acetobacter. Fungi in which sphingolipids have been found comprise Saccharomyces, Candida, Histoplasma, Phytophthora, Cryptococcus, Aspergillus, Neurospora, Schizosaccharomyces, Fusicoccum, Shizophyllum, Amanita, Hansenula, Lactarius, Lentinus, Penicillium, Clitocybe, Paracoccidioides, Agaricus, Sporothrix, and oomycete plant pathogens. The fact that sphingolipids are not universally present in bacteria and fungi makes them interesting as taxonomic markers. Thus in Sphingomonas spp. distinction by sphingolipid and fatty acid patterns is in agreement with phylogenetic clustering by 16 S rRNA gene sequences.