白念珠菌的菌体密度与生物被膜形成及tyrosol分泌  

The role of cell density in the morphology of the Candida albicans biofilms development and the tyrosoi production

作　　者：魏昕[1,2] 吴观陵[1] 刘卫红[2] 张琰[2] 胡琴[1] 

机构地区：[1]南京医科大学基础医学博士后流动站,210029 [2]南京医科大学口腔医学研究所

出　　处：《中华微生物学和免疫学杂志》2010年第4期344-348,共5页Chinese Journal of Microbiology and Immunology

基　　金：国家自然科学基金资助课题（30872885）;中国博士后基金资助课题（20080431118）;江苏省自然科学基金（BK2008361）

摘　　要：目的观察不同接种浓度条件下白念珠菌生被物膜的形成，研究菌体密度在白念珠菌生物被膜形成及密度感应分子tyrosol产生中的作用。方法白念珠菌标准株SC5314和临床株通过YPD增菌，细胞计数和梯度稀释将白念珠菌细胞悬液调配至5×10^6个／ml、5×10^5个／ml、5×10^4个／ml、5×10^3个／ml不同浓度，随后将不同浓度的白念珠菌接种到培养皿中，形成白念珠菌生物被膜。1、5、3、4．5、24、36h高效液相色谱检测白念珠菌tyrosol产生情况，在同样的时间点对生物被膜取样进行扫描电镜观察。结果菌体密度对白念珠菌生物被膜tyrosol产生存在作用；接种浓度低的白念珠菌分泌tyrosol少，接种浓度高的白念珠菌分泌tyrosol较多。生物被膜形成24h产生tyrosol最多，随后减低。菌体密度影响白念珠菌早期生物被膜的形成；扫描电镜观察到接种浓度低的白念珠菌细胞出芽少，分裂繁殖少；而接种浓度高的白念珠菌出芽较多，分裂繁殖更多；随着时间的延长，接种浓度高的情况下更早形成成熟生物被膜。结论菌体密度与白念珠菌生物被膜形成及tyrosol的产生之间存在相关性。Objective To study the role of cell density in the tyrosol production and morphology for Candida albicans biofilms. Methods C. albicans SC5314 and clinical isolates were propagated in yeast peptone dextrose （YPD） medium. Cells were collected by centrifugation and washed twice in sterile phosphate-buffered saline （PBS） before this study, then resuspended in RPMI 1640 supplemented with L-glutamine and adjusted to a desired concentration of 5 × 10^6 cells/ml, 5 × 10^5 cells/ml, 5 × 10^4 cells/ml, 5 × 10^3 cells/ml after counting with a hematocytometer. Standardized C. albicans cells were prepared as above description and 2000 pd of this standardized cell suspension was dispensed into the wells, then C. albicans biofilms were formed on the bottom of the polystyrene wells. In this study, tyrosol synthesized by SC5314 and clinical isolates of C. albicans biofilm was quantified by high performance liquid chromatography （ HPLC ）. The effects of tyrosol on morphology of C. albicans biofihns were investigated by scanning electron microscopy （SEM）. Results Tyrosol production of C. albicans biofilms was affected by cell densities. At lower inoculation size（5 × 10^3 cells/ml）, there was too less tyrosol production to be detected at the early stage of the biofilms formation. At higher inoculation size （5 × 10^6 cells/ml） , tyrosol can be detectable at the early stage or at the mature stage of biofilms formation. There was a sharp increase in tyrosol concentration at 24 h, while there was a decrease in tyrosol concentration after that time from the strains when the strains were at an inoculation size of 5 × 10^6 cells/ml and 5 × 10^5 cells/ml. Cell densities affected the morphology formation of the C. albicans biofilms. At the early stage of the biofilms formation, C. albicans grew less germ tube at lower cell densities than that at the higher cell densities. With the mature of the biofilms, C. albicans grew more hyphae at higher cell densities than that at the lower cell densities. All these abo

关 键 词：白念珠菌生物被膜 菌体密度 TYROSOL 

分 类 号：R379[医药卫生—病原生物学]