Study On Ultramicro-Morphology And Oxidative Morphological Character Of Penicillium Marneffei Parasited In Guangxi Wild Rhizomys Pruinosus And Clinical Isolate From Patient

Objective We observed the ultrastructure of dimorphic penicillium marneffei parasited in Guangxi wild Rhizomys pruinosus and clinical isolate before and after treated by hydrogen peroxide so as to explore the morphology characteristics and ultrastructural diversity after antioxidative injury between two different originated peniciltium marneffei.Methods We cultured the two penicillium marneffei in 25℃and 37℃for seven days,observed its feathers under optical microscope and ultrastructure under transmission electron microscope.We cultured the two penicillium marneffei with hydrogen peroxide in 25℃and 37℃for seven days.Then we differentiate its feathers under optical microscope and ultrastructure under transmission electron microscope.Results①Both of two different originated penicillium marneffei are mycelial in 25℃,there are rose pigment production,both aerial hypha and vegetative hyphae are abundant;when cultured in 37℃,white yeast colony like membrane can be seen.After treated by hydrogen peroxide, both of the two strains grew slowly,and both of them produced more pigment in mycelial phase when cultured in 25℃,further more, penicillium marneffei parasited in Rhizomys pruinosus had more vegetative hyphae than aerial hypha,while penicillium marneffei clinical isolates failed to show this feather;both different originated penicillium marneffei did not show obvious different appearances when cultured in media containing 2.0 mM hydrogen peroxide in 37℃.②Under optical microscope,both strains have branch,separate mycelium,conidiophore, single whorl or double whorl penicilli when cultured in 25℃;spherical,ellipse yeastlike cell and arthrospore can be seen when cultured in 37℃。After treated by hydrogen peroxide,When cultured in 25℃and observed under optical microscope,penicillium marneffei clinical isolated produced less spores,and some hyphae and brush sticks deformed.To penicillium marneffei parasited in Guangxi wild Rhizomys pruinosus, there are no difference after added hydrogen peroxide under optical microscope.Both different originated penicillium marneffei are crenation when cultured in media containing 2.0 mM hydrogen peroxide in 37℃.③When observed under transmission electron microscope before treated by hydrogen peroxide,it showed that the cell wall was smooth, membrane was integrital,cytoplasm often had a nucleus,mitochondria, endoplasmic reticulum,lipid body,vacuolars of all sizes.In 37℃, microbody and other organella in 25℃can be seen.While after treated by hydrogen peroxide,it showed that the wall was intact,even had some defects in partial wall,and thickness was uneven;the membrane was discontinuous and even had shrinkages and uplifts;cytoplasm was uneven,phagocytosis was obvious,mitochondria structural change, microbody also can be seen in 37℃.The organelle structure of the penicillium marneffei clinical isolate is fuzziness in 25℃,and In 37℃nucleus without nucleolemma,Apoptosis can be seen,change more obviously than that of thepenicillium marneffei parasited in Guangxi wild Rhizomys pruinosus.Conclusion①It showed no morphological differences between the two different originated strains under optical microscope and transmission electron microscope in diphase temperature.②There are changes in diphase temperature to the same strain.When observed under electron microscope,yeast phase had microbody while mycelium phase did not have.③After treated by hydrogen peroxide,the growth was inhibited in 25℃and the two strains produced more rose red pigment and showed some changes in ultrastructure,such as intact cell wall(CW), mitochondria degenerated;in 37℃microbody and degenerative mitochondria can be seen,phagocytosis phenomena is obviouse.④When cultrue in 37℃,perhaps penicillium marneffei can use microbody(Mb)to dissolve the old cell organelles then form phagotrophic vacuoles and adjust respiratory oxidation in mitochondria so as to maintain the stability of the inner environment and to resist oxidative damage.When a cell had more reactive oxidative species than detoxification and repair capacity, this would lead to cell injury even to death.When coping with identical oxidative stress,the ultrastructure of clinical isolate has more changes than that of the wild Rhizomys pruinosus parasited.This experiment indicates that the wild Rhizomys pruinosus parasitize has more oxidative stress than that of the clinical isolate.