التفاصيل البيبلوغرافية
| العنوان: |
Nonspecific Phospholipase C Activity from Listeria Monocytogenes is Activated by Phagosome Acidification |
| المؤلفون: |
Huang, Qiongying, Roberts, Mary |
| المساهمون: |
National Institutes of Health |
| المصدر: |
The FASEB Journal ; volume 27, issue S1 ; ISSN 0892-6638 1530-6860 |
| بيانات النشر: |
Wiley |
| سنة النشر: |
2013 |
| المجموعة: |
Wiley Online Library (Open Access Articles via Crossref) |
| الوصف: |
Broad‐range, phosphatidylcholine‐preferring phospholipase C (PC‐PLC LM ) from Listeria monocytogenes is one of the critical virulence factors mediating the dissolution of vacuolar membranes so that the intracellular pathogen can escape into the cytosol and spread to neighboring cells. We have expressed the enzyme in E. coli and characterized its kinetics with a variety of substrates. The amino acid sequence of PC‐PLC LM is highly homologous to Bacillus cereus PC‐PLC BC . Both are metalloenzymes with identical residues coordinating to the Zn 2+ ligands. Intriguingly, the PC‐PLC LM exhibits an acidic pH optimum (pH5~6) compared to the well‐studied PC‐PLC BC which is more efficient at basic pH values. This is significant as PC‐PLC LM activity is needed to aid in Listeria escape from acidified vacuolar pH. The optimal efficiency at acidic pH results from dramatically reduced K m values but moderate changes in k cat at lower pH. In addition, unlike PLC BC , PC‐PLC LM can cleave sphingomyelin. Mechanistic details for the acidic pH optimum and substrate specificity are probed with mutagenesis and a combination of biochemical and biophysical approaches. This study is supported by the National Institutes of Health GM60418. |
| نوع الوثيقة: |
article in journal/newspaper |
| اللغة: |
English |
| DOI: |
10.1096/fasebj.27.1_supplement.789.18 |
| الاتاحة: |
http://dx.doi.org/10.1096/fasebj.27.1_supplement.789.18 |
| Rights: |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
| رقم الانضمام: |
edsbas.1A15BCE8 |
| قاعدة البيانات: |
BASE |