Anoxybacillus flavithermus WK1

Anoxybacillus spp. are facultative anaerobes found in diverse moderate- to high-temperature habitats such as geothermal hot springs, manure and processed foods such as gelatin. Anoxybacillus flavithermus is a major contaminant of milk powder and gelatin. Strain WK1 (DSM 21510) was isolated from the waste water drain at the Wairakei geothermal power station in New Zealand. The bacterium is a dark yellow color which is caused by accumulation of a carotenoid pigment in the cell membrane. It is unusual in its ability to grow in waters that are super-saturated with amorphous silica, and where opaline silica sinter is actively forming. Sinter is a deposit of opaline or amorphous silica with small cavities that occurs as an incrustation around hot springs and geysers and sometimes forms conical mounds (geyser cones) or terraces. The ability of A. flavithermus to grow in super-saturated silica solutions makes it an ideal subject to study the processes of sinter formation, which might be similar to the biomineralization processes that occurred at the dawn of life. The genome shows clear signs of genome compaction in the Anoxybacilus/Geobacillus branch, compared to other members of the family Bacillaceae. Synthesis of long chain polyamines and biofilm formation by A. flavithermus could regulate sinter formation and control the textural features of the resulting siliceous sinters. The presence of an array of c-di-GMP-related signal transduction proteins suggests that A. flavithermus could regulate biofilm formation in response to the environmental conditions (adapted from PubMed 19014707 and Encyclopaedia Brittanica). (HAMAP: ANOFW)