Table 2.

Effect of chemical modification on RTX-III toxicity for mice [160,161,188,189,190,191].

Modified Residue(s)	Reagent	LD50 Modif./LD50 Nativ (Mice)
Gly1 (α-NH2) Lys4 Lys (C-terminal)	[3H]-acetic anhydride	12 2 2
Arg13	malonic aldehyde phenylglyoxal 1,2-cyclohexanedione	4–5
COOH	[3H]-glycine methyl ether/EDC [14C]-trimethyloxonium tetrafluoroborate	1–2
Trp30	2-hydroxy-5-nitrobenzyl bromide	1
S-S bonds	2-mercaptoethanol/iodoacetamide	>100