Kirchhoff Lisa, Weisner Ann-Kathrin, Schrepffer Mona, Hain Andrea, Scharmann Ulrike, Buer Jan, Rath Peter-Michael, Steinmann Joerg
Institute of Medical Microbiology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.
Institute of Clinical Hygiene, Medical Microbiology and Infectiology, Klinikum Nürnberg, Paracelsus Medical University, Nuremberg, Germany.
Front Microbiol. 2020 Mar 20;11:471. doi: 10.3389/fmicb.2020.00471. eCollection 2020.
Research into the cooperative pathogenicity of microbes in cystic fibrosis (CF) lungs is crucial for an understanding of the pathophysiology of infections and the development of novel treatment strategies. This study investigated the impact of the common CF-associated bacterial pathogen on the black yeast . It evaluated the planktonic growth, biofilm formation, morphology, and virulence of the fungus in the presence or absence of . It also determined the role of quorum-sensing (QS) molecules within these interactions, e.g., by using sterile culture filtrate and QS-deficient mutants. is known to inhibit the planktonic growth of . We found that fungal biofilm formation increased in the presence of after 24 h but is decreased significantly after 48 h. This effect was reversed when, instead of QS wild-type strains, ΔlasR, and ΔrhlR mutants were added to biofilm formation. The number and length of hyphae were substantially reduced when was co-cultivated with , but not when it was co-cultivated with the mutants. Experiments testing the virulence of in the greater wax moth showed a synergetic effect on larval killing when was injected together with culture filtrate. Survival rates were decreased when biofilm culture filtrate was added but not when planktonic culture filtrate was added. In summary, affects the growth, morphology, biofilm formation, and virulence of N-acyl-L-homoserine lactone (AHL) QS molecules regulated factors that have been shown to contribute to the inhibition of the ability of to form filaments and biofilm.
研究囊性纤维化（CF）肺部微生物的协同致病性对于理解感染的病理生理学和开发新的治疗策略至关重要。本研究调查了常见的CF相关细菌病原体对黑酵母的影响。它评估了在有或没有该细菌病原体的情况下真菌的浮游生长、生物膜形成、形态和毒力。它还确定了群体感应（QS）分子在这些相互作用中的作用，例如通过使用无菌培养滤液和QS缺陷突变体。已知该细菌病原体可抑制真菌的浮游生长。我们发现，在24小时后，真菌生物膜形成在有该细菌病原体的情况下增加，但在48小时后显著减少。当添加ΔlasR和ΔrhlR突变体而非QS野生型菌株时，这种影响在真菌生物膜形成中得到逆转。当该细菌病原体与真菌共培养时，菌丝的数量和长度大幅减少，但与突变体共培养时则不然。在大蜡螟中测试真菌毒力的实验表明，当真菌与该细菌病原体的培养滤液一起注射时，对幼虫死亡有协同作用。添加生物膜培养滤液时存活率降低，但添加浮游培养滤液时则不然。总之，该细菌病原体影响真菌的生长、形态、生物膜形成和毒力，N-酰基-L-高丝氨酸内酯（AHL）QS分子调节的因素已被证明有助于抑制真菌形成细丝和生物膜的能力。
