Analysis of natural diatom communities reveals novel insights into the diversity of long chain polyamine (LCPA) structures involved in silica precipitation

► First report of long chain polyamines (LCPAs) in frustules of natural mixed marine diatom populations. ► Astonishing variety of >100 natural LCPAs with complex distribution found in each plankton tow sample. ► Clear regional differences in molecular composition and structural characteristics. ► Sulfated LCPAs are produced by diatoms.