The gluconeogenesis pathway is involved in maintenance of enterohaemorrhagic Escherichia coli O157:H7 in bovine intestinal content.
The gluconeogenesis pathway is involved in maintenance of enterohaemorrhagic Escherichia coli O157:H7 in bovine intestinal content.
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DOI：
10.1371/journal.pone.0098367
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发表时间：
2014
期刊：
影响因子：
3.7
通讯作者：
Forano E
中科院分区：
文献类型：
--
作者：
Bertin Y;Deval C;de la Foye A;Masson L;Gannon V;Harel J;Martin C;Desvaux M;Forano E
肠出血性大肠杆菌（EHEC）是引起食源性和水源性疾病暴发的原因。牛胃肠道（GIT）被认为是EHEC的主要储存库。了解肠出血性大肠杆菌在牛肠道中生长和存活所必需的营养物质，可能有助于制定限制其在牛粪便中脱落的战略，从而降低人类患病的风险。为了确定动物GIT中诱导的特定代谢途径，比较了EHEC O 157：H7 EDL 933在牛小肠内容物（BSIC）和补充葡萄糖的基本培养基中孵育期间的转录组谱。转录组分析显示，负责乙醇胺，尿素，胍丁胺和氨基酸（天冬氨酸，苏氨酸，甘氨酸，丝氨酸和色氨酸）的同化基因强烈上调，这表明这些化合物是BSIC中EHEC的主要氮源。在BSIC中孵育的EHEC中，也明确了EHEC的代谢途径和代谢底物同化的核心作用。本研究结果表明，三种氨基酸（Asp、Ser和Trp）、甘油、甘油3-磷酸、L-乳酸和C4-二羧酸是BSIC中EHEC的重要碳源。使用产微生物底物作为氮源（氨基酸）和/或碳源（氨基酸、甘油和乳酸盐）的能力可以为肠液中的细菌提供生长优势。因此，BSIC中存在天冬氨酸（2.4 mM）、丝氨酸（1.9 mM）、甘油（5.8 mM）和乳酸（3.6 mM），可能代表EHEC可能使用的主要致肠出血性底物。E.构建了磷酸烯醇式丙酮酸合酶（PpsA）和磷酸烯醇式丙酮酸羧激酶（PckA）缺陷型、不能利用三羧酸（TCA）中间体的大肠杆菌（EDL 933）。EHEC EDL 933和BSIC中的同基因突变株之间的生长竞争实验清楚地显示了野生型菌株的显著竞争性生长优势，进一步说明了EHEC在牛GIT中维持EHEC的同源途径的重要性。
Enterohaemorrhagic Escherichia coli (EHEC) are responsible for outbreaks of food- and water-borne illness. The bovine gastrointestinal tract (GIT) is thought to be the principle reservoir of EHEC. Knowledge of the nutrients essential for EHEC growth and survival in the bovine intestine may help in developing strategies to limit their shedding in bovine faeces thus reducing the risk of human illnesses. To identify specific metabolic pathways induced in the animal GIT, the transcriptome profiles of EHEC O157:H7 EDL933 during incubation in bovine small intestine contents (BSIC) and minimal medium supplemented with glucose were compared. The transcriptome analysis revealed that genes responsible for the assimilation of ethanolamine, urea, agmatine and amino acids (Asp, Thr, Gly, Ser and Trp) were strongly up-regulated suggesting that these compounds are the main nitrogen sources for EHEC in BSIC. A central role for the gluconeogenesis pathway and assimilation of gluconeogenic substrates was also pinpointed in EHEC incubated in BSIC. Our results suggested that three amino acids (Asp, Ser and Trp), glycerol, glycerol 3-phosphate, L-lactate and C4-dicarboxylates are important carbon sources for EHEC in BSIC. The ability to use gluconeogenic substrates as nitrogen sources (amino acids) and/or carbon sources (amino acids, glycerol and lactate) may provide a growth advantage to the bacteria in intestinal fluids. Accordingly, aspartate (2.4 mM), serine (1.9 mM), glycerol (5.8 mM) and lactate (3.6 mM) were present in BSIC and may represent the main gluconeogenic substrates potentially used by EHEC. A double mutant of E. coli EDL933 defective for phosphoenolpyruvate synthase (PpsA) and phosphoenolpyruvate carboxykinase (PckA), unable to utilize tricarboxylic acid (TCA) intermediates was constructed. Growth competition experiments between EHEC EDL933 and the isogenic mutant strain in BSIC clearly showed a significant competitive growth advantage of the wild-type strain further illustrating the importance of the gluconeogenesis pathway in maintaining EHEC in the bovine GIT.
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影响因子：
5.1
作者：
Bertin, Yolande;Girardeau, J. P.;Martin, Christine
通讯作者：
Martin, Christine
影响因子：
3.2
作者：
Abo-Amer, AE;Munn, J;Andrews, SC
通讯作者：
Andrews, SC
影响因子：
4.4
作者：
Bergholz, Teresa M.;Vanaja, Sivapriya Kailasan;Whittam, Thomas S.
通讯作者：
Whittam, Thomas S.
影响因子：
3.2
作者：
ENGEL, P;KRAMER, R;UNDEN, G
通讯作者：
UNDEN, G
DOI：
10.1111/j.2517-6161.1995.tb02031.x
发表时间：
1995-01-01
影响因子：
5.8
作者：
BENJAMINI, Y;HOCHBERG, Y
通讯作者：
HOCHBERG, Y