UNASSIGNED: In this study, we used two pigmented (DSM 111179 and DSM 113836) and two non-pigmented S. capitis subsp. capitis strains (DSM 20326T and DSM 31028) to identify the pigment, determine conditions under which pigment-production occurs and investigate whether pigmented strains show increased resistance to ROS and temperature stress.
UNASSIGNED: We found that the non-pigmented strains remained colorless regardless of the type of medium, whereas intensity of pigmentation in the two pigmented strains increased under low nutrient conditions and with longer incubation times. We were able to detect and identify staphyloxanthin and its derivates in the two pigmented strains but found that methanol cell extracts from all four strains showed ROS scavenging activity regardless of staphyloxanthin production. Increased survival to cold temperatures (-20°C) was detected in the two pigmented strains only after long-term storage compared to the non-pigmented strains.
UNASSIGNED: The identification of staphyloxanthin in S. capitis is of clinical relevance and could be used, in the same way as in S. aureus, as a possible target for anti-virulence drug design.
■在这项研究中,我们使用了两种色素(DSM111179和DSM113836)和两种无色素的头螺旋藻。capitis菌株(DSM20326T和DSM31028)鉴定色素,确定发生色素产生的条件,并研究色素菌株是否显示出对ROS和温度胁迫的抗性增加。
■我们发现,无论培养基类型如何,非色素菌株都保持无色,而在低营养条件和更长的孵育时间下,两种色素菌株的色素沉着强度增加。我们能够在两种色素菌株中检测和鉴定紫光黄质及其衍生物,但发现所有四种菌株的甲醇细胞提取物均显示出清除ROS的活性,而与紫光黄质的产生无关。与非色素菌株相比,仅在长期储存后,在两种色素菌株中检测到对低温(-20°C)的存活率增加。
■头孢沙漏中的葡萄黄质的鉴定具有临床意义,可以使用,就像金黄色葡萄球菌一样,作为抗毒力药物设计的可能目标。