non-virulent

Numerous studies have shown that inhibiting a single adhesin in this coordinated effort can often be enough to make a pathogenic bacterium non-virulent.

Scientists have observed that non-virulent forms of HIV can give rise to virulent strains after serial passage occurs in primates.

Because deletions of some fas genes give a non-virulent phenotype, for fas a main role in virulence was proposed .

The technique showed that the antigenic proteins of the non-virulent E.muris is more post-translationally modified than the highly virulent IOE.

Non-virulent bacteria have also been shown to transform into highly virulent pathogens through lysogenic conversion with the with virulence factors carried on the lysogenic prophage.

Plowright used a mono-layer of kidney cells to culture the virus until it became non-virulent and could be transmitted from one cattle to another, producing lifelong immunity against rinderpest.

Gene transfer using it happens when "a restriction enzyme is used to cut non-virulent plasmid DNA derived from A. tumefaciens and thus create an insertion point, into which the gene can be ligated.

A form of "inoculation" or cross protection may also be used where seedlings are inoculated with a non-virulent strain of the virus (ZYMV-WK); this prevents infection with the severe strain.

In nature, such viruses are much less virulent than mutants of the same viruses that in laboratory culture readily out-compete non-virulent variants (or than tick-transmitted viruses, since ticks, unlike mosquitoes, do bite dead rabbits).

In researching a potential polio vaccine, he had focused on live viruses that were attenuated (rendered non-virulent) rather than on killed viruses (the latter became the basis for the injected vaccine that was subsequently created by Jonas Salk).

In this early experiment dead Streptococcus pneumoniae of the virulent strain type III-S, when injected along with living but non-virulent type II-R pneumococci, resulted in a deadly infection of type III-S pneumococci.