Abstract: The present invention provides methods for identifying bacteria by analysis of lipid A and/or lipoteichoic acid structure and/or mass spectrometry ionization patterns.

Abstract: The invention provides methods for identifying polypeptides. The method can include the steps of simultaneously determining the mass of a subset of parent polypeptides from a population of polypeptides and the mass of fragments of the subset of parent polypeptides; comparing the determined masses to an annotated polypeptide index; and identifying one or more polypeptides of the annotated polypeptide index having the determined masses. The method can further include the steps of determining one or more additional characteristics associated with one or more of the parent polypeptides; comparing the determined characteristics to the annotated polypeptide index; and optionally repeating the steps one or more times, wherein a set of characteristics is determined that identifies a parent polypeptide as a single polypeptide in the annotated polypeptide index. The method can additionally include the step of quantitating the amount of the identified polypeptide in a sample containing the polypeptide.

Abstract: The invention provides methods for identifying polypeptides. The method can include the steps of simultaneously determining the mass of a subset of parent polypeptides from a population of polypeptides and the mass of fragments of the subset of parent polypeptides; comparing the determined masses to an annotated polypeptide index; and identifying one or more polypeptides of the annotated polypeptide index having the determined masses. The method can further include the steps of determining one or more additional characteristics associated with one or more of the parent polypeptides; comparing the determined characteristics to the annotated polypeptide index; and optionally repeating the steps one or more times, wherein a set of characteristics is determined that identifies a parent polypeptide as a single polypeptide in the annotated polypeptide index. The method can additionally include the step of quantitating the amount of the identified polypeptide in a sample containing the polypeptide.

Abstract: The present invention relates generally to mass spectrometry. The present invention relates more particularly to methods and systems for use in mass spectrometric identification of a variety of analytes, including high molecular weight species such as proteins. One embodiment of the invention is a method for analyzing an analyte. The method includes nebulizing a suspension of the analyte in a solvent with a surface acoustic wave transducer; and performing mass spectrometry on the nebulized suspension. The surface acoustic wave transducer can be used, for example, to transfer non-volatile peptides and proteins (as well as other analyztes, such as oligonucleotides and polymers) to the gas phase at atmospheric pressure. Nebulization using surface acoustic waves can be conducted in a discontinuous or pulsed mode, similar to that used in MALDI, or in a continuous mode, as in ESI.

Abstract: The present invention relates generally to mass spectrometry. The present invention relates more particularly to methods and systems for use in mass spectrometric identification of a variety of analytes, including high molecular weight species such as proteins. One embodiment of the invention is a method for analyzing an analyte. The method includes nebulizing a suspension of the analyte in a solvent with a surface acoustic wave transducer; and performing mass spectrometry on the nebulized suspension. The surface acoustic wave transducer can be used, for example, to transfer non-volatile peptides and proteins (as well as other analyztes, such as oligonucleotides and polymers) to the gas phase at atmospheric pressure. Nebulization using surface acoustic waves can be conducted in a discontinuous or pulsed mode, similar to that used in MALDI, or in a continuous mode, as in ESI.

Abstract: The present invention relates generally to mass spectrometry. The present invention relates more particularly to methods and systems for use in mass spectrometric identification of a variety of analytes, including high molecular weight species such as proteins. One embodiment of the invention is a method for analyzing an analyte. The method includes nebulizing a suspension of the analyte in a solvent with a surface acoustic wave transducer; and performing mass spectrometry on the nebulized suspension. The surface acoustic wave transducer can be used, for example, to transfer non-volatile peptides and proteins (as well as other analyztes, such as oligonucleotides and polymers) to the gas phase at atmospheric pressure. Nebulization using surface acoustic waves can be conducted in a discontinuous or pulsed mode, similar to that used in MALDI, or in a continuous mode, as in ESI.

Abstract: The present invention provides methods for identifying bacteria by analysis of lipid A and/or lipoteichoic acid structure and/or mass spectrometry ionization patterns.

Abstract: The present invention relates generally to mass spectrometry. The present invention relates more particularly to methods and systems for use in mass spectrometric identification of a variety of analytes, including high molecular weight species such as proteins. One embodiment of the invention is a method for analyzing an analyte. The method includes nebulizing a suspension of the analyte in a solvent with a surface acoustic wave transducer; and performing mass spectrometry on the nebulized suspension. The surface acoustic wave transducer can be used, for example, to transfer non-volatile peptides and proteins (as well as other analyztes, such as oligonucleotides and polymers) to the gas phase at atmospheric pressure. Nebulization using surface acoustic waves can be conducted in a discontinuous or pulsed mode, similar to that used in MALDI, or in a continuous mode, as in ESI.

Abstract: The invention provides a method of determining an amino acid sequence of a parent polypeptide. The method consists of: (a) obtaining mass spectra of two or more differentially labeled polypeptide fragments of a parent polypeptide; (b) assigning a mass and a weighting characteristic to two or more paired signals having a difference in mass corresponding to an integer value of said differential label, the weighting characteristic combining properties of each signal within said paired signals; (c) selecting from the mass spectra a paired signal having the assigned mass and a weighting characteristic distinguishable from non-peptide signals, the assigned mass indicating the mass of a polypeptide fragment within the spectra; (d) determining the difference in mass of the polypeptide fragments; (e) assigning the mass differences a satisfying amino acid name, and (f) orienting the assigned amino acid names. Also provided is a method of determining the amino acid sequence of a polypeptide.

Abstract: The present invention provides methods and reagents for identifying specific masses of compounds in a complex mixture. In particular, the present invention describes an isotope distribution encoded tag (IDEnT) concept wherein the ability to distinguish an analyte encoded with a non-native isotope from those not encoded with the isotope or from those encoded with a different isotope is used for protein identification, enzyme active site identification, peptide sequencing, and the like. Reagents used in the IDEnT strategy consist of a chemical element with a unique isotope distribution not normally found in the analyte class being studied, chemically bonded to, or an integral part of a chemical reagent with a high selectivity of affinity for specific functional group in the analyte.

Abstract: The invention provides a method of determining an amino acid sequence of a parent polypeptide. The method consists of: (a) obtaining mass spectra of two or more differentially labeled polypeptide fragments of a parent polypeptide; (b) assigning a mass and a weighting characteristic to two or more paired signals having a difference in mass corresponding to an integer value of said differential label, the weighting characteristic combining properties of each signal within said paired signals; (c) selecting from the mass spectra a paired signal having the assigned mass and a weighting characteristic distinguishable from non-peptide signals, the assigned mass indicating the mass of a polypeptide fragment within the spectra; (d) determining the difference in mass of the polypeptide fragments; (e) assigning the mass differences a satisfying amino acid name, and (f) orienting the assigned amino acid names. Also provided is a method of determining the amino acid sequence of a polypeptide.

Abstract: The invention provides methods for identifying a polypeptide. The method can include determining two or more characteristics associated with the polypeptide, or a fragment thereof, one of the characteristics being mass of a fragment of the polypeptide, the fragment mass being determined by mass spectrometry; comparing the characteristics associated with the polypeptide to an annotated polypeptide index; and identifying one or more polypeptides in the annotated polypeptide index having the characteristics. The method can further include the steps of determining one or more additional characteristics associated with the polypeptide; comparing the determined characteristics to the annotated polypeptide index; optionally repeating the steps one or more times, wherein a set of characteristics is determined that identifies a single polypeptide in the annotated polypeptide index, and optionally quantitating the amount of identified polypeptide in a sample containing the polypeptide.

Abstract: The invention provides methods for identifying polypeptides. The method can include the steps of simultaneously determining the mass of a subset of parent polypeptides from a population of polypeptides and the mass of fragments of the subset of parent polypeptides; comparing the determined masses to an annotated polypeptide index; and identifying one or more polypeptides of the annotated polypeptide index having the determined masses. The method can further include the steps of determining one or more additional characteristics associated with one or more of the parent polypeptides; comparing the determined characteristics to the annotated polypeptide index; and optionally repeating the steps one or more times, wherein a set of characteristics is determined that identifies a parent polypeptide as a single polypeptide in the annotated polypeptide index. The method can additionally include the step of quantitating the amount of the identified polypeptide in a sample containing the polypeptide.