Identification of bacterial species and subspecies using lipids

Abstract

The use of free, extractable lipids found in bacteria for identification of bacterial species and subspecies is described. Bacteria have been found to differ sufficiently in their extracted lipid compositions to effect identification using thin layer chromatographic techniques. Burkholderia pseudomallei, Burkholderia thailandensis, and Burkholderia mallei have been distinguished in this manner. Lipopeptides specific to Mycobacterium avium subspecies paratuberculosis, but not to the closely related bacterium Mycobacterium avium subspecies avium have also been used as a basis for bacterial subspecies identification using mass spectrometry and seroreactivity. Mass spectrometric analysis of total bacterial lipids of Burkholderia pseudomallei, Burkholderia thailandensis, and Burkholderia mallei, and mass spectrometric analysis of total bacterial lipids for Mycobacterium avium subspecies paratuberculosis and Mycobacterium avium subspecies avium, without further lipid separation, has shown that species and subspecies of bacteria may be identified using such analysis.

Description

RELATED CASES [0001] The present patent application claims the benefit of Provisional Patent Application Ser. No. 60 / 856,188 filed on Nov. 2, 2006 and entitled “Major Cell Wall Lipopeptide Of Mycobacterium Avium Subspecies” by Torsten M. Eckstein et al., which application is hereby incorporated by reference herein for all that it discloses and teaches.STATEMENT REGARDING FEDERAL RIGHTS [0002] This invention was made with government support under Contract Numbers: P01-AI-046393; P01-AI-057836; R01-AI-033706; R01-AI-051283; R01-AI-053796; U54-AI-065357; and R37-AI-018357, awarded by the National Institute of Allergy and Infectious Diseases of the U.S. National Institutes of Health to Colorado State University; Contract Number 2004-35605-14243 USDA / CSREES, awarded by the U.S. Department of Agriculture Coop State Research and Extension Service to Colorado State University; and Contract Number Q6286224112 from the Johne's Disease Integrated Program (JDIP) awarded as a subcontract from th...

AI Technical Summary

Benefits of technology

[0013] Still another object of the invention is to provide a method for identifying bacterial species with a reduced number of false negatives.

Problems solved by technology

Bacteria are often detected in the context of the disease they cause, but few infectious diseases are sufficiently specific that a physician can treat them directly.

Indirect identification methods have the disadvantage of identifying other bacteria instead of the actual pathogen due to cross-reactivity of the extracts, fraction, or whole bacteria.

Therefore, such tests only provide a first step for identification.

However, such tests have not been proven to be species-, subspecies-, or type-specific, and thus, share the same disadvantages as exist for whole extracts or fractions of whole bacteria (that is, cross-reactivity, as an example).

Comparative methods for chromosomal DNA and proteins have been developed to distinguish these species, but these molecules are not generally useful because of their low efficiency in specific techniques (DNA in PCR amplification, or cross-reactivity in hybridization techniques), or due to the large number of similar molecules within the proteome (several thousand molecules may have to be compared as a result of separation techniques having poor efficiency).

However, methods for successful separation of saccharides are not yet available.

Since these tests are multi-factorial, false-negative data that cannot be proven to be correct may result, and the tests do not have a “backup” target to verify a negative result.

However, in many situations the original sequence is not known and amplification processes cannot be performed.

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