Virulence-related genotypic differences among Bacillus cereus ocular and gastrointestinal isolates and the relationship to endophthalmitis pathogenesis.
Virulence-related genotypic differences among Bacillus cereus ocular and gastrointestinal isolates and the relationship to endophthalmitis pathogenesis.
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DOI：
10.3389/fcimb.2023.1304677
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发表时间：
2023
影响因子：
5.7
通讯作者：
中科院分区：
文献类型：
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蜡状芽孢杆菌（Bc）可引起自限性胃肠道感染，但当感染眼睛时，可引起快速和不可逆的失明。本研究调查了临床眼部和胃肠道Bc分离株在毒力相关基因型和眼内炎毒力方面是否存在差异。评估了28株Bc眼部、胃肠道和实验室参考分离株。进行溶血试验以评估溶血活性的潜在差异。通过PCR检测了20个Bc毒力相关基因的存在。在实验性眼内炎小鼠模型中，将5种毒力基因PCR阳性的眼部和胃肠道分离株亚组与菌株ATCC 14579进行比较。在感染后8小时，通过视网膜电图评估视网膜功能，并通过平板计数确定眼内细菌浓度。胃肠道Bc分离株比Bc眼部分离株和ATCC 14579更具溶血性（p < 0.0001）。与胃肠道分离株相比，Bc眼部分离株的capK、cytK、hblA、hblC和plcR PCR阳性频率更高（p ≤ 0.0002）。在眼内炎模型中，感染ATCC 14579的眼睛与感染选定眼部或胃肠道分离株的眼睛之间的平均A波保留无显著差异（p ≥ 0.3528）。观察到平均B波保留的结果相似（p ≥ 0.0640）。与ATCC 14579相比，只有一种大肠杆菌分离株显示出显著更大的B波保留（p = 0.0303）。在选定的眼部和胃肠道分离株之间，未观察到平均A波（p ≥ 0.1535）或B波（p ≥ 0.0727）保留的显著差异。ATCC 14579的眼内浓度显著高于选定的眼部分离株和3种胃肠道分离株（p ≤ 0.0303）。选定眼部分离株的眼内浓度与胃肠道分离株无显著差异（p ≥ 0.1923）。在评估的毒性相关基因子集中，与胃肠道分离株相比，眼部分离株中有5个基因显着富集。虽然胃肠道分离株的溶血活性较高，但所选眼部和胃肠道分离株之间的视网膜功能保留和眼内生长没有显著差异。这些结果表明，Bc菌株引起胃肠道感染，而不同的溶血活性和毒力相关的基因谱的眼分离株，类似的毒力在眼内炎。
Bacillus cereus (Bc) can cause self-limiting gastrointestinal infections, but when infecting the eye, can cause rapid and irreversible blindness. This study investigated whether clinical ocular and gastrointestinal Bc isolates differed in terms of virulence-related genotypes and endophthalmitis virulence. Twenty-eight Bc ocular, gastrointestinal, and laboratory reference isolates were evaluated. Hemolysis assays were performed to assess potential differences in hemolytic activity. The presence of twenty Bc virulence-related genes was assessed by PCR. A subset of ocular and gastrointestinal isolates differing in PCR positivity for 5 virulence genes was compared to strain ATCC14579 in an experimental murine model of endophthalmitis. At 8 hours post infection, retinal function was evaluated by electroretinography, and intraocular bacterial concentrations were determined by plate counts. Gastrointestinal Bc isolates were more hemolytic than the Bc ocular isolates and ATCC14579 (p < 0.0001). Bc ocular isolates were more frequently PCR-positive for capK, cytK, hblA, hblC, and plcR compared to the gastrointestinal isolates (p ≤ 0.0002). In the endophthalmitis model, mean A-wave retention did not differ significantly between eyes infected with ATCC14579 and eyes infected with the selected ocular or gastrointestinal isolates (p ≥ 0.3528). Similar results were observed for mean B-wave retention (p ≥ 0.0640). Only one diarrheal isolate showed significantly greater B-wave retention when compared to ATCC14579 (p = 0.0303). No significant differences in mean A-wave (p ≥ 0.1535) or B-wave (p ≥ 0.0727) retention between the selected ocular and gastrointestinal isolates were observed. Intraocular concentrations of ATCC14579 were significantly higher than the selected ocular isolate and 3 of the gastrointestinal isolates (p ≤ 0.0303). Intraocular concentrations of the selected ocular isolate were not significantly different from the gastrointestinal isolates (p ≥ 0.1923). Among the subset of virulence-related genes assessed, 5 were significantly enriched among the ocular isolates compared to gastrointestinal isolates. While hemolytic activity was higher among gastrointestinal isolates, retinal function retention and intraocular growth was not significantly different between the selected ocular and gastrointestinal isolates. These results suggest that Bc strains causing gastrointestinal infections, while differing from ocular isolates in hemolytic activity and virulence-related gene profile, are similarly virulent in endophthalmitis.
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影响因子：
2
作者：
Callegan, Michelle C.;Cochran, Daniel C.;Stroman, David W.
通讯作者：
Stroman, David W.
影响因子：
3.1
作者：
Callegan, MC;Booth, MC;Gilmore, MS
通讯作者：
Gilmore, MS
影响因子：
3.6
作者：
BASTIN, DA;STEVENSON, G;REEVES, PR
通讯作者：
REEVES, PR
影响因子：
2.1
作者：
Ehling-Schulz, Monika;Guinebretiere, Marie-Helene;Svensson, Birgitta
通讯作者：
Svensson, Birgitta
影响因子：
3.7
作者：
Fagerlund, Annette;Dubois, Thomas;Gohar, Michel
通讯作者：
Gohar, Michel