Linked Life Data

19735442

Source:http://linkedlifedata.com/resource/pubmed/id/19735442

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-9-29
pubmed:abstractText
alpha-Glucans such as starch and glycogen are abundant in the human oropharynx, the main site of group A Streptococcus (GAS) infection. However, the role in pathogenesis of GAS extracellular alpha-glucan binding and degrading enzymes is unknown. The serotype M1 GAS genome encodes two extracellular proteins putatively involved in alpha-glucan binding and degradation; pulA encodes a cell wall anchored pullulanase and amyA encodes a freely secreted putative cyclomaltodextrin alpha-glucanotransferase. Genetic inactivation of amyA, but not pulA, abolished GAS alpha-glucan degradation. The DeltaamyA strain had a slower rate of translocation across human pharyngeal epithelial cells. Consistent with this finding, the DeltaamyA strain was less virulent following mouse mucosal challenge. Recombinant AmyA degraded alpha-glucans into beta-cyclomaltodextrins that reduced pharyngeal cell transepithelial resistance, providing a physiologic explanation for the observed transepithelial migration phenotype. Higher amyA transcript levels were present in serotype M1 GAS strains causing invasive infection compared with strains causing pharyngitis. GAS proliferation in a defined alpha-glucan-containing medium was dependent on the presence of human salivary alpha-amylase. These data delineate the molecular mechanisms by which alpha-glucan degradation contributes to GAS host-pathogen interaction, including how GAS uses human salivary alpha-amylase for its own metabolic benefit.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1365-2958
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
74
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
159-74
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Contribution of AmyA, an extracellular alpha-glucan degrading enzyme, to group A streptococcal host-pathogen interaction.
pubmed:affiliation
Department of Infectious Diseases, MD Anderson Cancer Center, Houston, TX 77030, USA. sshelburne@mdanderson.org
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural