3IJT

Structural Characterization of SMU.440, a Hypothetical Protein from Streptococcus mutans

Replaces:  2B79

Summary for 3IJT

• Entry DOI: 10.2210/pdb3ijt/pdb
• Descriptor: Putative uncharacterized protein (2 entities in total)
• Functional Keywords: hypothetical protein, unknown function
• Biological source: Streptococcus mutans
• Total number of polymer chains: 2
• Total formula weight: 34853.00

Authors

Nan, J.,Brostromer, E.,Kristensen, O.,Su, X.-D. (deposition date: 2009-08-05, release date: 2009-08-25, Last modification date: 2024-03-20)

Primary citation

Nan, J.,Brostromer, E.,Liu, X.-Y.,Kristensen, O.,Su, X.-D.
Bioinformatics and structural characterization of a hypothetical protein from Streptococcus mutans: implication of antibiotic resistance
Plos One, 4:e7245-e7245, 2009

PubMed Abstract: As an oral bacterial pathogen, Streptococcus mutans has been known as the aetiologic agent of human dental caries. Among a total of 1960 identified proteins within the genome of this organism, there are about 500 without any known functions. One of these proteins, SMU.440, has very few homologs in the current protein databases and it does not fall into any protein functional families. Phylogenetic studies showed that SMU.440 is related to a particular ecological niche and conserved specifically in some oral pathogens, due to lateral gene transfer. The co-occurrence of a MarR protein within the same operon among these oral pathogens suggests that SMU.440 may be associated with antibiotic resistance. The structure determination of SMU.440 revealed that it shares the same fold and a similar pocket as polyketide cyclases, which indicated that it is very likely to bind some polyketide-like molecules. From the interlinking structural and bioinformatics studies, we have concluded that SMU.440 could be involved in polyketide-like antibiotic resistance, providing a better understanding of this hypothetical protein. Besides, the combination of multiple methods in this study can be used as a general approach for functional studies of a protein with unknown function.

PubMed: 19798411
DOI: 10.1371/journal.pone.0007245

Experimental method

X-RAY DIFFRACTION (2.377 Å)