TABLE 1.

Environmental PhaC genotypes found in extreme physicochemical conditions.

Ecosystem Type	Extreme ecosystem subtype or habitat descriptors	Bacteria PhaC			Archaea PhaC
		Class I	Class II	Class III	Class III
Marine	Deep oceanic, basalt-hosted subsurface hydrothermal fluid, Hydrothermal vents	3	2	4	3
	Deep-sea				3
	Creosote-contaminated soil			1
Non-marine saline and alkaline		40	2	21	44
Thermal springs		15	1	11	7
Geologic	Acid Mine	2
	Saline water, Salt, and Salt mine	4			3
Oil reservoir		1
Mud volcano			1
Rock-dwelling	Halite pinnacle				55
Soil	Creosote-contaminated soil			1
	Desert soil	1		1
	Permafrost sediment			1
	Saline				3
Subtotal (Relative abundance)		66	6	40	118
		(8.6%)	(5.3%)	(10.8%)	(57.8%)

Descriptors are taken from GOLD metadata under the ecosystem subtype or habitat headings. Ecosystems with no descriptors inherently contain extreme conditions.