Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

AI-2 compounds and analogs based on Salmonella typhimurium LsrB structure

a technology of ai-2 and ai-2 compound, which is applied in the field of crystals comprising apolsrb and hololsrb, can solve the problems of inaccurate use of s-thmf-borate to refer exclusively to ai-2 and difficulty in identifying the active form of ai-2 signaling in v. harveyi, etc., and achieve the effect of inhibiting ai-2 activity

Inactive Publication Date: 2006-10-12
THE TRUSTEES FOR PRINCETON UNIV
View PDF5 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

"The present invention is about crystals that contain a specific molecule called apo-LsrB or holo-LsrB, which are involved in quorum sensing, a process used by bacteria to communicate with each other. The crystals have been found to diffract X-rays to a high resolution, and the methods described in the invention can be used to identify potential ligands that can bind to LsrB. These ligands can be tested for their ability to affect quorum sensing and can be used to treat bacterial infections. The invention also includes pharmaceutical compositions containing these compounds and methods for regulating the activity of AI-2 receptors."

Problems solved by technology

Because DPD exists in equilibrium with other chemical species in solution (this work and Meijler et al., 2004), identifying the form that is active in AI-2 signaling in V. harveyi proved difficult.
These findings mean that the earlier use of the term “AI-2” to refer exclusively to S-THMF-borate is not accurate.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • AI-2 compounds and analogs based on Salmonella typhimurium LsrB structure
  • AI-2 compounds and analogs based on Salmonella typhimurium LsrB structure
  • AI-2 compounds and analogs based on Salmonella typhimurium LsrB structure

Examples

Experimental program
Comparison scheme
Effect test

example 1

Experimental Procedures

A. LsrB Production

[0091]S. typhimurium LsrB without its amino-terminal signal peptide (residues 1-26) was cloned into plasmid pGEX4T1 for expression as a glutathione-S-transferase (GST) fusion protein in E. coli strain BL21. Protein expression was induced by the addition of 0.1 mM isopropyl β-D-thiogalactopyranoside for 6 hr prior to harvesting the bacteria. The GST-LsrB fusion protein was purified by glutathione agarose affinity chromatography. The GST tag was removed by thrombin digestion, leaving two additional residues at the N terminus (GlySer) of LsrB. The protein was further purified by hydrophobic affinity chromatography (Phenyl Superose; Pharmacia) and size-exclusion chromatography (Superdex 200; Pharmacia). LsrB (>95% pure) was concentrated for crystallization experiments to 8 mg / ml in 20 mM Tris-HCl (pH 8.0), 150 mM NaCl, and 1 mM dithiothreitol. Selenomethionyl protein was overexpressed in E. coli B834. Cells were grown in M9 medium as described...

example 2

Structure of LsrB

[0103] The structure of S. typhimurium LsrB was determined to 2.1 Å resolution using multiwavelength anomalous diffraction (MAD) phasing and subsequently refined to 1.9 Å resolution (Table 1). Despite low sequence identity (11%), LsrB exhibits the same fold as the V. harveyi AI-2 signaling receptor LuxP (Chen et al., 2002), with a three-stranded hinge connecting two similar α / β domains (FIG. 2A). LsrB also has strong structural homology with several other sugar binding proteins including E. coli ribose binding protein (RBP) and S. typhimurium galactose binding protein, as well as repressors such as E. coli purine nucleotide synthesis repressor and trehalose repressor (Hars et al., 1998; Mowbray et al., 1992; Mowbray et al., 1983; Schumacher et al., 1994). In periplasmic binding proteins, including LuxP, the ligand binding site is near the hinge between the two domains. In the crystal structure of LsrB, the domains are in an open conformation similar to, though less...

example 3

Structure of the LsrB:Ligand Complex

[0104] To identify the LsrB ligand, LsrB was crystallized in the presence of DPD and the other products generated by incubating SAH with recombinant Pfs and LuxS enzymes as previously described (Schauder et al., 2001) (FIG. 1A). The structure was determined by molecular replacement and refined to 1.3 Å resolution (Table 1). In this structure, the domains of LsrB have closed around the binding site, rotating shut about the hinge region by 21° relative to one another (FIG. 2B) (Hayward et al., 2002). Nonprotein electron density is prominent between the two domains (FIG. 2C) in a location analogous to the ligand binding sites of LuxP and other periplasmic binding proteins. As detailed below, this electron density is consistent with R-THMF, a DPD derivative not previously known to be biologically active (FIGS. 2D and 2E).

[0105] The LsrB ligand R-THMF differs from the V. harveyi LuxP ligand S-THMF-borate in two respects (FIG. 3A). First, no borate is...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
pHaaaaaaaaaa
pHaaaaaaaaaa
pHaaaaaaaaaa
Login to View More

Abstract

This invention relates to crystals comprising apo-LsrB and holo-LsrB. The structure of holo-LsrB identifies a tetrahydroxytetrahydrofuran derived from 4,5-dihydroxy-2,3-pentanedione (DPD) as the active autoinducer-2 (AI-2) molecule in Salmonella typhimurium. The X-ray crystallographic data can be used in a drug discovery method. Additionally the invention provides AI-2 analogs based on this discovery as well as pharmaceutical compositions containing those analogs.

Description

[0001] This application claims benefit under 35 U.S.C. § 119(e) of U.S. Provisional Ser. No. 60 / 561,659, filed Apr. 12, 2004, which is incorporated herein by reference in its entirety.GOVERNMENT INTERESTS [0002] This invention was funded in part through a grant from the National Institutes of Health. Therefore, the federal government has certain rights in this invention.FIELD OF THE INVENTION [0003] This invention relates to crystals comprising apo-LsrB and holo-LsrB. The structure of holo-LsrB identifies a tetrahydroxytetrahydrofuran derived from 4,5-dihydroxy-2,3-pentanedione (DPD) as the active autoinducer-2 (AI-2) molecule in Salmonella typhimurium. The X-ray crystallographic data can be used in a drug discovery method. Additionally the invention provides AI-2 analogs based on this discovery as well as pharmaceutical compositions containing those analogs. BACKGROUND OF THE INVENTION [0004] Many bacteria modulate their behavior in response to cell-cell communication in a process ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(United States)
IPC IPC(8): G06F19/00A61K31/70C07K14/255A61K38/00
CPCA61K38/00C07H3/02C07K2299/00C07K14/255C07H7/02A61P33/04Y02A50/30
Inventor MILLER, STEPHENXAVIER, KARINATAGA, MLCHIKOCAMPAGNA, SHAWNSEMMELHACK, MARTINBASSLER, BONNIEHUGHSON, FREDERICK
Owner THE TRUSTEES FOR PRINCETON UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com