US5064756A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Microbial susceptibility assay using 7-n-(aminoacyl)-7-amido-4-methylcoumarins
Assignee: Siemens Healthcare Diagnostics Inc
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Filing: 1990-06-20
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Granted: 1991-11-12
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Expires: 2010-06-20
Abstract
Abstract A method of determining the susceptibility of microorganisms to an antimicrobial substance wherein the microorganisms are cultured in the presence of the antimicrobial substance, and growth or lack of growth is assessed by detecting a fluorescent product resulting from the enzymatic hydrolysis of a fluorogenic substrate. The fluorogenic substrates include 7-N-(aminoacyl)-7-amido-4-methylcoumarin, 7-N-(alanyl)-7-amido-4-methylcoumarin, or a combination of 7-N-(alanyl)-7-amido-4-methylcoumarin and 4-methyl umbelliferyl phosphate.
Inventors
- 👤 Anthony H. Carr
- 👤 Robert A. Badley
- 👤 Ian Jobling
- 👤 Thomas J. Sands
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:01
CPC Classifications
C; C12; C12Q; C12Q1/00; C12Q1/02; C12Q1/18; C12Q1/04; C12Q2334/00; C12Q2334/20; C12Q2334/22; C12Q2337/00; C12Q2337/20; C12Q2337/22; Y; Y10; Y10S; Y10S436/00; Y10S436/80; Y10S436/805
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
77 words
In a method of determining the susceptibility of microorganisms to an antimicrobial substance, comprising culturing the microorganisms in the presence of an antimicrobial substance, contacting the microorganisms with a fluorogenic substrate which is enzymatically hydrolyzable to yield a fluorescent product, and determining growth by measuring the fluorescent product yielded by the hydrolysis of the fluorescent substrate, wherein the improvement comprises using as said fluorogenic substrate a 7-N-(aminoacyl)-7-amido-4-methylcoumarin and exposing the microorganisms to the fluorescent substrate throughout culturing.
Claim 2
Dependent Claim
77 words
In a method of determining the susceptibility of microorganisms to an antimicrobial substance, comprising culturing the microorganisms in the presence of an antimicrobial substance, contacting the microorganisms with a fluorogenic substrate which is enzymatically hydrolyzable to yield a fluorescent product, and determining growth by measuring the fluorescent product yielded by the hydrolysis of the fluorescent substrate, wherein the improvement comprises using as said fluorogenic substrate a 7-N-(aminoacyl)-7-amido-4-methylcoumarin and exposing the microorganisms to the fluorescent substrate throughout culturing.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein the microorganisms are initially present at a concentration of 5×10 4 to 4×10 6 microorganisms per ml.
Claim 4
Dependent Claim
18 words
The method of claim 1 wherein the microorganisms are cultured for a period of 3.5 to 7 hours.
Claim 5
Dependent Claim
56 words
The method of claim 1 further comprising culturing the microorganisms in the presence of the fluorogenic substrate in a plurality of culture vessels, wherein the culture vessels contain serial dilutions of the antimicrobial substance and wherein growth or lack of growth of the microorganisms is used to determine the minimum inhibitory concentration of the antimicrobial substance.
Claim 6
Dependent Claim
67 words
In a method of determining the susceptibility of microorganisms to an antimicrobial substance, comprising culturing the microorganisms in the presence of an antimicrobial substance, contacting the microorganisms with a fluorogenic substrate which is enzymatically hydrolyzable to yield a fluorescent product, and determining growth by measuring the fluorescent product yielded by the hydrolysis of the fluorescent substrate, wherein the improvement comprises using as said fluorogenic substrate a 7-N-(alanyl)-7-amido-4-methylcoumarin.
Claim 7
Dependent Claim
67 words
In a method of determining the susceptibility of microorganisms to an antimicrobial substance, comprising culturing the microorganisms in the presence of an antimicrobial substance, contacting the microorganisms with a fluorogenic substrate which is enzymatically hydrolyzable to yield a fluorescent product, and determining growth by measuring the fluorescent product yielded by the hydrolysis of the fluorescent substrate, wherein the improvement comprises using as said fluorogenic substrate a 7-N-(alanyl)-7-amido-4-methylcoumarin.
Claim 8
Dependent Claim
16 words
The method of claim 5 further comprising exposing the microorganisms to the fluorescent substrate throughout culturing.
Claim 9
Dependent Claim
23 words
The method of claim 6 wherein the microorganisms are initially present at a concentration of 5×10 4 to 4×10 6 microorganisms per ml.
Claim 10
Dependent Claim
73 words
In a method of determining the susceptibility of microorganisms to an antimicrobial substance, comprising culturing the microorganisms in the presence of an antimicrobial substance, contacting the microorganisms with a fluorogenic substrate which is enzymatically hydrolyzable to yield a fluorescent product, and determining growth by measuring the fluorescent product yielded by the hydrolysis of the fluorescent substrate, wherein the improvement comprises using as said fluorogenic substrate a combination of 7-N-(aminoacyl)-7-amido-4-methylcoumarin and 4-methyl umbelliferyl phosphate.
Claim 11
Dependent Claim
73 words
In a method of determining the susceptibility of microorganisms to an antimicrobial substance, comprising culturing the microorganisms in the presence of an antimicrobial substance, contacting the microorganisms with a fluorogenic substrate which is enzymatically hydrolyzable to yield a fluorescent product, and determining growth by measuring the fluorescent product yielded by the hydrolysis of the fluorescent substrate, wherein the improvement comprises using as said fluorogenic substrate a combination of 7-N-(aminoacyl)-7-amido-4-methylcoumarin and 4-methyl umbelliferyl phosphate.
Claim 12
Dependent Claim
16 words
The method of claim 8 further comprising exposing the microorganisms to the fluorescent substrate throughout culturing.
Claim 13
Dependent Claim
23 words
The method of claim 9 wherein the microorganisms are initially present at a concentration of 5×10 4 to 4×10 6 microorganisms per ml.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-11-11 | 1995-05-13 | 1995-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-11 | 1999-05-13 | 1999-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-11 | 2003-05-13 | 2003-11-12 | $7700.00 | Window Closed / Lapsed |