Academic Journal
Osmotic regulation of the aqpZ water channel gene in E. coli
| العنوان: | Osmotic regulation of the aqpZ water channel gene in E. coli |
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| المؤلفون: | CALAMITA, Giuseppe, B. KEMPF, M. BONHIVERS, W. R. BISHAI, S. KNEIP, K. E. RUDD, E. BREMER, P. AGRE |
| المساهمون: | Calamita, Giuseppe, B., Kempf, M., Bonhiver, W. R., Bishai, S., Kneip, K. E., Rudd, E., Bremer, P., Agre |
| سنة النشر: | 1998 |
| المجموعة: | Università degli Studi di Bari Aldo Moro: CINECA IRIS |
| مصطلحات موضوعية: | Aquaporin, Bacteria, Osmoregulation, Water transport |
| الوصف: | Osmotic movement of water across bacterial cell membranes is postulated to be a homeostatic mechanism for maintaining cell turgor. The molecular water transporter remained elusive until discovery of the Escherichia coli water channel, AqpZ, however the regulation of the aqpZ gene expression and physiological function of the AqpZ protein are unknown. Northern analysis revealed a transcript of 0.7 kb, confirming the monocistronic nature of aqpZ. Regulatory studies performed with an aqpZ::lacZ low copy plasmid demonstrate enhanced expression during mid-logarithmic growth, and expression of the gene is dependent upon the extracellular osmolality, which increased in hypoosmotic environments but strongly reduced in hyperosmolar NaCl or KCl. While disruption of the chromosomal aqpZ is not lethal for E. coli, the colonies of the aqpZ knockout mutant are smaller than those of the parental wild-type strain. When cocultured with parental wild-type E. coli, the aqpZ knockout mutant exhibits markedly reduced colony formation when grown at 39°C. Similarly, the aqpZ knockout mutant also exhibits greatly reduced colony formation when grown at low osmolality, but this phenotype is reversed by overexpression of AqpZ protein. These results implicate AqpZ as a participant in the adaptive response of E. coli to hypoosmotic environments and indicate a requirement for AqpZ by rapidly growing cells. |
| نوع الوثيقة: | article in journal/newspaper |
| اللغة: | English |
| Relation: | info:eu-repo/semantics/altIdentifier/wos/000072848500056; volume:95; issue:7; firstpage:3627; lastpage:3631; numberofpages:5; journal:PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA; http://hdl.handle.net/11586/74120; info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-0032584246 |
| DOI: | 10.1073/pnas.95.7.3627 |
| الاتاحة: | http://hdl.handle.net/11586/74120 https://doi.org/10.1073/pnas.95.7.3627 |
| رقم الانضمام: | edsbas.9DA68879 |
| قاعدة البيانات: | BASE |
| DOI: | 10.1073/pnas.95.7.3627 |
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