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Series GSE37099 Query DataSets for GSE37099
Status Public on Apr 01, 2015
Title Porphyromonas gingivalis 33277 wild-type vs Fur orthologue Har isogenic mutant ECR455
Platform organism Porphyromonas gingivalis W83
Sample organism Porphyromonas gingivalis ATCC 33277
Experiment type Expression profiling by array
Summary Porphyromonas gingivalis is a major pathogen associated with the microbial biofilm-mediated disease chronic periodontitis. P. gingivalis has an obligate requirement for iron and protoporphyrin IX which it satisfies by transporting heme and iron liberated from the human host. The level of cellular iron in P. gingivalis affects the expression of a distinct iron-associated regulon of 64 genes and low iron invokes an iron sparing response. Iron homeostasis is usually mediated in Gram-negative bacteria at the transcriptional level by the Ferric Uptake Regulator (Fur). There is a single predicted P. gingivalis Fur superfamily orthologue named Har (heme associated regulator) that lacks the conserved metal binding residues found in other Fur orthologues. We show that Har binds both heme and ferrous iron resulting in a conformational change in the protein. Har was unable to complement the Escherichia coli H1780 fur mutant and there was no change in cellular metal content in a P. gingivalis Har mutant compared with the wild-type. The Har regulon of 44 genes is not predicted to play a role in iron homeostasis. Together these data indicated that Har does not regulate iron homeostasis in P. gingivalis. However, Har was required for heme-responsive biofilm development and its regulon overlapped P. gingivalis regulons previously identified after growth in heme limitation or as a homotypic biofilm. P. gingivalis is unique as an iron-dependent Gram-negative bacterium with a single heme-binding Fur superfamily orthologue, Har, that does not regulate iron homeostasis.
 
Overall design Paired samples were compared on the same microarray using a two-colour system. A total of 6 paired microarray hybridizations were performed representing 6 biological replicates, where a balanced dye design was used, with the overall analysis including three microarrays where P. gingivalis 33277 samples were labeled with Cy3 and the paired ECR455 samples were labeled with Cy5 and three other microarrays where samples were labeled with the opposite combination of fluorophores.
 
Contributor(s) Butler CA, Mitchell HL, Dashper SG, Reynolds EC
Citation(s) 25375181, 26484248
Submission date Apr 09, 2012
Last update date Jul 29, 2019
Contact name Catherine Butler
E-mail(s) cbutler@unimelb.edu.au
Phone 61-3-93411565
Organization name The University of Melbourne
Department The Melbourne Dental School
Lab The Reynolds Lab
Street address 720 Swanston St
City Carlton
State/province VIC
ZIP/Postal code 3053
Country Australia
 
Platforms (1)
GPL1438 PFGRC Porphyromonas gingivalis 70 mer oligo array.
Samples (6)
GSM910675 fur_mutant_rep1 vs. 33277_rep1
GSM910676 fur_mutant_rep2 vs. 33277_rep2
GSM910677 fur_mutant_rep3 vs. 33277_rep3
Relations
BioProject PRJNA158399

Download family Format
SOFT formatted family file(s) SOFTHelp
MINiML formatted family file(s) MINiMLHelp
Series Matrix File(s) TXTHelp

Supplementary file Size Download File type/resource
GSE37099_RAW.tar 8.9 Mb (http)(custom) TAR (of GPR)
Processed data included within Sample table

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