Prevalence of the Genes Encoding Propionicin T1 and Protease-Activated Antimicrobial Peptide and Their Expression in Classical Propionibacteria
Prevalence of the Genes Encoding Propionicin T1 and Protease-Activated Antimicrobial Peptide and Their Expression in Classical Propionibacteria
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经典丙酸杆菌中丙酸素T1和蛋白酶激活抗菌肽基因的流行及其表达
DOI：
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发表时间：
2004
影响因子：
4.4
通讯作者：
H. Holo
中科院分区：
文献类型：
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作者：
T. Faye;D. Brede;T. Langsrud;I. Nes;H. Holo
摘要 本研究的目的是调查 64 个经典丙酸杆菌分离株中细菌素丙酸素 T1 和蛋白酶激活抗菌肽 (PAMP) 的产生频率及其相应基因。这项研究表明，这些基因在詹氏丙酸杆菌和特氏丙酸杆菌中广泛存在，但在所研究的其余经典丙酸杆菌物种中不存在。在 63% 的詹氏 P. 菌株和 61% 的 P. thoenii 菌株中发现了前 PAMP 编码基因 (pamA)，并且所有这些菌株都表现出 PAMP 活性。 89% 的 P. thoenii 菌株和 54% 的 P. jensenii 菌株中存在丙酸素 T1 编码基因 (pctA)。所有含有 pctA 基因的 P. thoenii 菌株都表现出与丙酸素 T1 活性相对应的抗菌活性，而只有 38% 的含有 pctA 的 P. jensenii 菌株表现出这种活性。 pctA 基因测序揭示了 6 个詹氏青霉菌株中存在两个等位基因变体，它们在单个核苷酸上存在差异；在这些菌株中，丙酸素 T1 的 55 位甘氨酸被天冬氨酸残基取代（A 变体）。没有携带 A 变体的菌株对丙酸素 T1 敏感细菌表现出任何抗菌活性。位于 pctA 基因下游的开放阅读框 (orf2) 在含有丙酸 T1 G 变体的三个菌株中不存在。其中两个菌株显示出较低的抗菌活性，而第三个菌株则根本没有显示出抗菌活性。 orf2编码的蛋白与ABC转运蛋白表现出很强的同源性，之前有人提出该蛋白参与针对丙酸素T1的生产者免疫。缺乏orf2的菌株表现出的有限抗菌活性进一步表明这种假定的ABC转运蛋白在丙酸素T1活性中发挥着重要作用。
ABSTRACT The purpose of this study was to investigate the frequency of production of the bacteriocin propionicin T1 and the protease-activated antimicrobial peptide (PAMP) and their corresponding genes in 64 isolates of classical propionibacteria. This study revealed that these genes are widespread in Propionibacterium jensenii and Propionibacterium thoenii but absent from the remaining species of classical propionibacteria that were studied. The pro-PAMP-encoding gene (pamA) was found in 63% of the P. jensenii strains and 61% of the P. thoenii strains, and all of these strains displayed PAMP activity. The propionicin T1-encoding gene (pctA) was present in 89% of the P. thoenii strains and 54% of the P. jensenii strains. All P. thoenii strains containing the pctA gene exhibited antimicrobial activity corresponding to propionicin T1 activity, whereas only 38% of the pctA-containing P. jensenii strains displayed this activity. Sequencing of the pctA genes revealed the existence of two allelic variants that differed in a single nucleotide in six strains of P. jensenii; in these strains the glycine at position 55 of propionicin T1 was replaced by an aspartate residue (A variant). No strains harboring the A variant showed any antimicrobial activity against propionicin T1-sensitive bacteria. An open reading frame (orf2) located immediately downstream from the pctA gene was absent in three strains containing the G variant of propionicin T1. Two of these strains showed low antimicrobial activity, while the third strain showed no antimicrobial activity at all. The protein encoded by orf2 showed strong homology to ABC transporters, and it has been proposed previously that this protein is involved in the producer immunity against propionicin T1. The limited antimicrobial activity exhibited by the strains lacking orf2 further suggests that this putative ABC transporter plays an important role in propionicin T1 activity.
影响因子：
17.3
作者：
Hancock, REW;Lehrer, R
通讯作者：
Lehrer, R