Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Reexamination Certificate
2000-06-02
2004-03-09
McKane, Joseph K. (Department: 1626)
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C549S230000
Reexamination Certificate
active
06703513
ABSTRACT:
BACKGROUND OF THE INVENTION
Autoinducers (“AIs”) are extracellular signal compounds used by a variety of bacteria to regulate cellular functions in response to changes in population density. For example, light production by the marine symbiotic bacterium
Vibrio fischeri
is controlled in a population density-responsive manner by the self-produced, membrane-permeable autoinducer, N-3-oxohexanoyl-L-homoserine lactone (N-3-oxohexanoyl-L-HSL; AI-1). AI-1 accumulates in a population density-dependent manner during bacterial growth. When it reaches a threshold concentration, AI-1, via the autoinducer receptor and transcriptional activator, LuxR, activates transcription of the lux operon, luxICDABEG, which encodes autoinducer synthase (luxI) and luminescence enzymes. (Eberhard et al.,
Biochemistry
20: 2444-2449 (1981); Engebrecht et al. Cell, 32: 773-781 (1983); Engebrecht et al.,
Proc. Natl. Acad. Sci. USA
81: 4154-4158 (1984); Hanzelka et al.,
J. Bacteriol.
177: 815-817 (1995); Shadel et al.,
J. Bacteriol.
172: 3980-3987 (1990); Slock et al.,
J. Bacteriol.,
172:3974-3979 (1990); Swartzman et al.,
J. Bacteriol.
172: 6797-6802 (1990)). The autoinduction mechanism in
V. fischeri
also involves, among other regulatory aspects, an AI-1 mediated luxR negative autoregulation (Dunlap et al.,
J. Bacteriol.
170: 4040-4046 (1988); Dunlap et al.,
J. Bacterial.
171: 3546-3552 (1989); Engebrecht et al.,
Genet. Eng.
8: 31-44 (1986); Shadel et al.,
J. Bacteriol.
173: 568-574 (1991); Shadel et al.,
J. Biol. Chem.
267: 7690-7695 (1992)).
Long thought to be a regulatory mechanism unique to the luminescence system of
V. fischeri
and certain closely related marine luminous bacteria, autoinduction of gene expression recently has been identified in a wide variety of other bacteria (Fuqua et al.,
J. Bacteriol.
176:269-275(1994)). The diversity of species using autoinduction and the chemical and genetic similarities of their autoinduction systems indicate that autoinduction is an evolutionary conserved regulatory mechanism commonly used by bacteria to sense and respond to population density.
All bacteria presently known to utilize AIs associate with higher organisms, i.e., plants and animals, at some point during their lifecycles. For example,
Pseudomonas aeruginosa
is an opportunistic pathogen in humans with cystic fibrosis. P. aerugitiosa regulates various virulence determinants with AI (Davies et al. Science 280: 295 (1998)). Other examples of Al producing bacteria include
Erwinia carotovora, Pseudomonas aureofaciens, Yersinia enterocolitica, Vibrio harveyi
, and
Agrobacterium tumefaciens. E. carotovora
infects certain plants and creates enzymes that degrade the plant's cell walls, resulting in what is called “soft rot disease.”
E. carotovora
produces the autoinducer N-3-oxohexanoyl-L-HSL.
Yersinia enterocolitica
is a bacterium, which causes gastrointestinal disease in humans and has been reported to produce an autoinducer.
P. aureofaciens
associates with the roots of plants and produces antibiotics that block fungus growth in the roots. That antibiotic synthesis is under autoinducer control.
In addition to the known naturally occurring autoinducers, recent work has focused on the synthesis and testing of synthetic analogues of certain autoinducers. For example, Bycroft et al., U.S. Pat. No. 5,593,827 have synthesized a series of N-(&bgr;-ketocaproyl)-L-homoserine lactone derivatives. The homoserine lactone derivatives are active autoinducers and control gene expression in certain organisms. Additionally, the autoinducer analogue N-(3-oxo-dodecanoyl)-homoserine lactone has been shown to inhibit the activity of
P. aeruginosa
(Pearson et al., U.S. Pat. No. 5,591,872). Furthermore, autoinducer analogues based on a furanone ring structure have been shown to inhibit homoserine lactone regulated processes in microorganisms (Kjellberg et al., WO 96/29392). Cao and coworkers have synthesized a series of N-acyl homoserine lactones and assessed their binding parameters and structure-function relationship in the
V. harveyi
lux system. None of these references describes the synthesis of autoinducer analogues that are suitable for attachment to other molecules and surfaces.
Autoinducer molecules are thought to have particular relevance in the progression of cystic fibrosis (CF). CF is the most common inheritable lethal disease among Caucasians. There are approximately 25,000 CF patients in the U.S.A. The frequency of CF in several other countries (e.g., Canada, United Kingdom, Denmark) is high (ranging from 1 in 400 to 1 in 1,600 live births).
Chronic respiratory infections caused by mucoid
Pseudomonas aeruginosa
are the leading cause of high morbidity and mortality in CF. The initially colonizing
P. aeruginosa
strains are nonmucoid but in the CF lung they inevitably convert into the mucoid form. The mucoid coating composed of the exopolysaccharide alginate leads to the inability of patients to clear the infection, even under aggressive antibiotic therapies. The emergence of the mucoid form of
P. aeruginosa
is associated with further disease deterioration and poor prognosis.
The microcolony mode of growth of
P. aeruginosa
, embedded in exopolysaccharide biofilms in the lungs of CF patients (Lam et al.,
Infect. Immun.
28: 546 (1980)), among other functions, plays a role in hindering effective opsonization and phagocytosis of
P. aeruginosa
cells (Pier et al.,
N. Engl. J. Med.
317: 793-8 (1987); Pier et al., Infect Immun. 60: 4768-76 (1992)). Although CF patients can produce opsonic antibodies against
P. aeruginosa
antigens, in most cases phagocytic cells cannot effectively interact with such opsonins (Pressler et al.,
Clin. Exp. Immunol.
90: 209-14 (1992); Pier et al.,
Science
249: 537-40 (1990)). Physical hindrance caused by the exopolysaccharide alginate and a functionally important receptor-opsonin mismatch caused by chronic inflaztnation and proteolysis are contributing factors to the ineffective interactions (Tosi et al.,
J. Infect. Dis.
162: 156-62 (1990)). Moreover, the biofilm prevents the effective delivery of exogenous antimicrobial agents to the microorganisms of the colony (de Beer et al.,
Appl. Environ. Microbiol.
60: 4339 (1994)).
Compounds and compositions facilitating the study of autoinduction mechanisms, particularly biofilm formation, arid which are effective in disrupting biofilms or retarding their formation would represent a significant advance in the treatment of disease states associated with biofilms, such as CF. Quite surprisingly, the present invention provides such compounds and compositions.
SUMMARY OF THE INVENTION
Thus, in a first aspect, the present invention provides a compound having a structure according to Formula I:
wherein, R
1
is preferably a member selected from —H, —OH, and (═O); R
2
is preferably a member selected from reactive functional groups, alkyl groups terminally substituted with a reactive functional group and internally substituted alkyl groups terminally substituted with a reactive functional group; X is preferably a member selected from —O—, —S— and —NH—; and X
1
and X
2
are preferably members independently selected from O and S.
In a second aspect, the present invention provides a compound having the structure according to Formula II:
wherein, R
1
is preferably a member selected from H, OH, and (═O), and R
2
is preferably a member selected from reactive functional groups, alkyl groups terminally substituted with a reactive functional group and internally substituted alkyl groups terminally substituted with a reactive functional group.
In a third aspect, the present invention provides a compound having a structure that is a member selected from:
wherein, m is preferably a number selected from 1 to 20, inclusive; n is preferably a number from 0 to 20, inclusive; and Z is a reactive functional group.
In a fourth aspect, the invention provides an immobilized compound comprising a solid support to which is attached a molecule comprising a structure according to Formula VI:
wherei
K-Quay Enterprises LLC
McKane Joseph K.
Small Andrea D.
Townsend and Townsend / and Crew LLP
LandOfFree
Production and use of derivatized homoserine lactones does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Production and use of derivatized homoserine lactones, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Production and use of derivatized homoserine lactones will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3247250