Metabolite Of Nocardia Farcinica After Induction Of Celegans Inhibits The Incubation Of Eggs Laid By C.elegans

Nocardia farcinica is a kind of gram-positive bacteria which lives in soil and is saprophytic and oxybiontic. It can form slender aerial hyphae and performs as yellow bacterial colony accompanied with the formation of typical wrinkle on the culture plate.Immunocompromised host or host of restrainable type will get nocardiosis through local or spreading infection caused by inhalation of Nocardia farcinica. Caenorhabditis elegans is a type of worm that can live independently and feed on microbe,such as Escherichia coli.In the condition of20degrees in the laboratory,the life cycle of C. elegans is only three days and a half.The developmental phase of these worms can be divided into three parts:embryonic stage,larval stage and adult stage.Hermaphrodite of autogamy can generate about300offsprings.Now,because of some advantages such as the simpleness of genetic manipulation and the short life cycle, C. elegans has become a model of researching the interaction between microbe-host and natural immunity.In this paper, we studied whether Nocardia farcinica infect C. elegans.Results show that L4can grow to adults and lay eggs after feeding on Nocardia farcinica,but these eggs can not be incubated.This phenomenon is a new acting way between microbe and nematodes and is not yet be reported.We suppose that a kind or some kinds of secondary metabolites of Nocardia farcinica have played a key role in this.Further researches reveal that,the active material which can inhibit the hatching of eggs should be induced by live C.elegans growing on Nocardia farcinica and this material can directly suppress the hatching of eggs instead of being ate by C.elegans.We also found that the active material which can inhibit the hatching of eggs has small polarity and present to be oleosus and can be dissolved in petroleum ether,chloroform,acetone,methyl alcohol and other organic solvents.To be interesting,one sort of secondary metabolite of Nocardia farcinica(Maybe it is the same material with the active material which can inhibit the hatching of eggs) can kill the larvae1of C. elegans and the larvae2of M. Incognita.