TiFN, Wageningen, The Netherlands.
Microbiology, Department of Biology, Utrecht University, Utrecht, The Netherlands.
PLoS Genet. 2022 Jun 15;18(6):e1010086. doi: 10.1371/journal.pgen.1010086. eCollection 2022 Jun.
Penicillium roqueforti is a major food-spoilage fungus known for its high resistance to the food preservative sorbic acid. Here, we demonstrate that the minimum inhibitory concentration of undissociated sorbic acid (MICu) ranges between 4.2 and 21.2 mM when 34 P. roqueforti strains were grown on malt extract broth. A genome-wide association study revealed that the six most resistant strains contained the 180 kbp gene cluster SORBUS, which was absent in the other 28 strains. In addition, a SNP analysis revealed five genes outside the SORBUS cluster that may be linked to sorbic acid resistance. A partial SORBUS knock-out (>100 of 180 kbp) in a resistant strain reduced sorbic acid resistance to similar levels as observed in the sensitive strains. Whole genome transcriptome analysis revealed a small set of genes present in both resistant and sensitive P. roqueforti strains that were differentially expressed in the presence of the weak acid. These genes could explain why P. roqueforti is more resistant to sorbic acid when compared to other fungi, even in the absence of the SORBUS cluster. Together, the MICu of 21.2 mM makes P. roqueforti among the most sorbic acid-resistant fungi, if not the most resistant fungus, which is mediated by the SORBUS gene cluster.
青霉（Penicillium roqueforti）是一种主要的食物腐败真菌，以对食品防腐剂山梨酸具有高抗性而闻名。在这里，我们证明当 34 株青霉（Penicillium roqueforti）在麦芽提取物肉汤中生长时，未解离山梨酸的最小抑制浓度（MICu）在 4.2 至 21.2 mM 之间。全基因组关联研究表明，最具抗性的 6 株菌株含有 180 kbp 的 SORBUS 基因簇，而其他 28 株菌株则没有。此外，SNP 分析显示，SORBUS 簇外的 5 个基因可能与山梨酸抗性有关。在抗性菌株中进行部分 SORBUS 敲除（超过 180 kbp 的 100），使山梨酸抗性降低到与敏感菌株相似的水平。全基因组转录组分析显示，在存在弱酸的情况下，抗性和敏感青霉（Penicillium roqueforti）菌株中都存在一小部分基因表达存在差异。这些基因可以解释为什么与其他真菌相比，青霉（Penicillium roqueforti）对山梨酸的抗性更强，即使没有 SORBUS 基因簇也是如此。总的来说，21.2 mM 的 MICu 使得青霉（Penicillium roqueforti）成为最耐山梨酸的真菌之一，如果不是最耐山梨酸的真菌，这是由 SORBUS 基因簇介导的。
