Modified Monosaccharide Labeling for Gram-Negative Bacteria
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for labeling living bacteria, particularly Gram-negative bacteria, lack specificity and efficiency in incorporating modified monosaccharide compounds into their outer membrane polysaccharides, such as LPS, which limits their ability to penetrate and metabolize within bacterial cells.
Innovation Solution
The use of modified monosaccharide compounds with specific reactive groups that can be metabolized into endogenous monosaccharides within the bacterial cell, allowing for incorporation into the outer membrane polysaccharides and subsequent labeling through click chemistry reactions, enabling specific labeling of bacteria like Legionella pneumophila.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If modified monosaccharide compounds with reactive groups are used for labeling bacteria, then labeling specificity and sensitivity are improved, but the complexity of the method and chemical synthesis requirements increase
Solution Approach 1:
The patent uses modified monosaccharide compounds as intermediary substances that bacteria naturally incorporate into their LPS through metabolic pathways. These intermediaries carry reactive groups (azide or alkyne) that enable subsequent click chemistry labeling without requiring direct modification of the bacteria themselves, thus improving specificity while managing complexity through biochemical mediation
Solution Approach 2:
The patent changes the chemical parameters of monosaccharide compounds by introducing reactive groups (azide -N3 or alkyne -C≡CH) at specific positions (C-3, C-4, C-6) of the sugar structure. This parameter modification allows the compounds to be metabolized by bacteria into labeled forms while maintaining compatibility with natural metabolic pathways, achieving high labeling specificity
2Productivity
If traditional culture-based methods are used for bacterial identification, then the method is simple and reliable, but the detection time is long and productivity is low
Solution Approach 1:
The patent performs preliminary action by pre-modifying monosaccharide compounds with reactive groups before introducing them to bacteria. These pre-modified compounds are then rapidly incorporated into bacterial LPS through natural metabolic pathways, enabling quick detection within hours rather than days required by culture methods, thus improving productivity while maintaining specificity
Solution Approach 2:
The patent replaces the mechanical/cultural system of traditional bacterial cultivation and identification with a chemical-biological system based on metabolic incorporation of modified sugars and click chemistry detection. This substitution dramatically reduces detection time from days to hours while enhancing specificity through the unique reactivity of the incorporated modified sugars
3Reliability
If modified monosaccharide compounds are incorporated into bacterial LPS, then specific labeling of bacteria is achieved, but the difficulty of chemical synthesis and purification of the modified compounds increases
Solution Approach 1:
The patent segments the synthesis process into modular steps: (1) synthesis of core monosaccharide structures with specific stereochemistry, (2) introduction of reactive groups at designated positions (C-3, C-4, or C-6), and (3) purification to obtain the modified compounds. This segmentation makes the complex synthesis more manageable and reproducible, improving reliability while systematically addressing synthesis challenges
Solution Approach 2:
The patent uses protecting groups and temporary modifications as intermediary steps during synthesis to facilitate the introduction of reactive groups at specific positions. These intermediaries enable selective modification without affecting other functional groups, making the synthesis more reliable and easier to execute
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method allows for rapid and specific labeling of Gram-negative bacteria, including Legionella pneumophila, with high sensitivity and specificity, enabling quicker identification and detection compared to traditional culture-based methods, and can differentiate between bacterial serogroups.
Implementation Method 1
The compound of formula (I) can be metabolized in a modified endogenous monosaccharide of the ulosonic acid type
Implementation Method 2
contacting said bacteria with a labeling molecule comprising a second reactive group, for generating the reaction of said first reactive group of said analog residue incorporated within said glycans of the outer membrane of said living bacteria with said second reactive group of said labeling molecule
Data Source
Figure 1(A)~1(C)
Figure 2
Figure 3
AI summary
The invention relates to a method for labeling specifically living bacteria of a given category of Gram negative bacteria in a sample comprising bacteria, the method comprising the steps of: a) incubating said bacteria of said sample with at least one modified monosaccharide compound comprising a first reactive chemical group capable to react with a second reactive group, so that a monosaccharide residue bearing said first reactive group is incorporated into the polysaccharides of the outer membrane of such bacteria, and b) contacting said modified monosaccharide residue incorporated within the outer membrane of the bacteria, with a labeling molecule comprising a said second reactive group. The said modified monosaccharide compound is a compound having the following formula (I), or a salt thereof: Wherein X can be O, NH or S, R1, R2 and R3 can be independently H, OH, NH2, OH and NH2 being substituted or not by protecting groups thereof, and R4 is H or an alkyl chain in C1 to C4 each carbon being substituted or not by OH or NH2 substituted or not by protecting groups thereof and at least one of X, R1, R2, R3 and R4 groups being substituted by a said first reactive group R'1.