Table 2. Demonstration of the role of the HPI in the grazing resistance.

Strain	IAI51 pCP1	+	+	++
	IAI51 irp-	+++	++++	++++
	IAI51	−	+	−
	606	+++++	+++++	+++++
		1	2	3
		log(number amoeba)

Bacterial lysis plaques (strains REL 606, IAI51, IAI51 irp-, IAI51 pCP1) observed six days after plating. A density of 10⁸ bacteria was plated with 10, 10² and 10³ amoebae. (+) represents the number of replicates with lysis plaques, (−) means no replicate showing plaques.