"Bacterial cell surfaces possess net negative electrostatic charge by virtue of ionized phosphoryl and carboxylate substituents on outer cell envelope macromolecules which are exposed to the extracellular environment . For example, Gram-negative bacteria have an outer layer of lipopolysaccharide (LPS) and protein which forms a highly charged surface that is stabilized by cation binding . Variations in the structure and chemical composition of the LPS have been shown to affect bacterial surface charge and the ability of bacteria to adhere to both glass and polystyrene surfaces . LPS can occur in two general forms, a hydrophobic (A form) and a charged hydrophilic (B form) [4667-4669].* Most protozoan  and bacterial cells [4671-4674] are negatively charged to varying degrees, though there are a few rare instances of positively-charged bacteria such as S. maltophilia . Bacterial negative charge can be reduced by Antibiotics
[4675, 4676], and complete bacterial charge reversal, from negative to positive, has been observed in the presence of certain metals and high pH [4677, 4678]. Note that the internal bacterial proton gradient does not affect the external charge.**"
"complete bacterial charge reversal, from negative to positive, has been observed in the presence of certain metals and high pH [4677, 4678"
"4677. Y.E. Collins, G. Stotzky, “Heavy metals alter the electrokinetic properties of bacteria, yeasts, and clay minerals,” Appl. Environ. Microbiol. 58(May 1992):1592-1600."
"4678. Y.E. Collins, G. Stotzky, “Changes in the surface charge of bacteria caused by heavy metals do not affect survival,” Can. J. Microbiol. 42(July 1996):621-627."
Is that sure enough?
If heavy metals alter the electrokinetic properties of bacteria, yeasts, and clay minerals then some of them who have that skill may have positive instead of negative charge and not be recognised by Miracle-Mineral-Supplement
Just a thought since we all know the relation between Candida and Mercury just as an example.