Abstract: Multimeric protected fluorescent reagents and their methods of synthesis are provided. The reagents are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The reagents contain fluorescent dye elements, that allow the compounds to be detected with high sensitivity at desirable wavelengths, binding elements, that allow the compounds to be recognized specifically by target biomolecules, and protective shield elements, that decrease undesirable contacts between the fluorescent dye elements and the bound target biomolecules and that therefore decrease photodamage of the bound target biomolecules by the fluorescent dye elements. The reagents also contain coupling elements connect monomeric compounds into multimeric forms, thereby increasing brightness.

Abstract: Protected fluorescent reagent compounds and their methods of synthesis are provided. The compounds are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The compounds contain fluorescent dye elements, that allow the compounds to be detected with high sensitivity at desirable wavelengths, binding elements, that allow the compounds to be recognized specifically by target biomolecules, and protective shield elements, that decrease undesirable contacts between the fluorescent dye elements and the bound target biomolecules and that therefore decrease photodamage of the bound target biomolecules by the fluorescent dye elements.

Abstract: Real time electronic sequencing methods, devices, and systems are described. Arrays of nanoFET devices are used to provide sequence information about a template nucleic acid in a polymerase-template complex bound to the nanoFET. A sequencing reaction mixture comprising nucleotide analogs having conductivity labels is introduced to the array of nanoscale electronic elements comprising nanoFETs under conditions of polymerase mediated nucleic acid synthesis. The polymerase enzyme template complex is attached to the gate of the nanoFET in an orientation whereby the nucleotide exit region of the polymerase enzyme is directed toward the gate of the nanoFET. Methods for producing nanoFET arrays are provided.

Abstract: Compositions, methods, and systems are provided for nucleotide analogs comprising protein shields for improving enzyme photostability in single molecule real time sequencing. Nucleotide analogs of the invention have a protein shield between the dye moieties and nucleotide moieties of the analog. The nucleotide analogs have two avidin proteins connected by a central dye component, and each avidin protein is further connected to a nucleotide component. The protein can prevent the direct interaction of the dye moiety with the enzyme carrying out nucleotide synthesis preventing photodamage to the enzyme. The nucleotide analogs of the invention can have multiple dyes and multiple nucleotide moieties.

Abstract: Sequencing methods, devices, and systems are described. Arrays of nanoscale electronic elements comprising two electrodes separated by an insulating layer are used to provide sequence information about a template nucleic acid in a polymerase-template complex bound proximate to the insulating region. A sequencing reaction mixture comprising nucleotide analogs having impedance labels is introduced to the array of nanoscale electronic elements under conditions of polymerase mediated nucleic acid synthesis. The time sequence of incorporation of nucleotide analogs is determined by identifying the types of labels of the nucleotide analogs that are incorporated into the growing strand using measured impedance.

Abstract: Protected fluorescent reagent compounds and their methods of synthesis are provided. The compounds are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The compounds contain fluorescent dye elements, that allow the compounds to be detected with high sensitivity at desirable wavelengths, binding elements, that allow the compounds to be recognized specifically by target biomolecules, and protective shield elements, that decrease undesirable contacts between the fluorescent dye elements and the bound target biomolecules and that therefore decrease photodamage of the bound target biomolecules by the fluorescent dye elements.

Abstract: The present invention provides methods, compositions, and systems for distributing molecules and complexes into reaction sites. In particular, the methods, compositions, and systems of the present invention result in an active loading of molecules and complexes into reaction sites with improved efficiency over loading by passive diffusion methods alone.

Abstract: Compositions, kits, methods and systems for single molecule nucleotide sequencing comprising producing polymerase reactions having lithium that control the median pulse width for incorporated nucleotides are disclosed. The levels of lithium are used to control pulse width while allowing other sequencing parameters to remain within a desirable range.

Abstract: Provided are compositions comprising recombinant DNA polymerases that include amino acid substitutions, insertions, deletions, and/or exogenous features that confer modified properties upon the polymerase for enhanced single molecule sequencing. Such properties can include enhanced metal ion coordination, reduced exonuclease activity, reduced reaction rates at one or more steps of the polymerase kinetic cycle, decreased branching fraction, altered cofactor selectivity, increased yield, increased thermostability, increased accuracy, increased speed, increased readlength, and the like. Also provided are nucleic acids which encode the polymerases with the aforementioned phenotypes, as well as methods of using such polymerases to make a DNA or to sequence a DNA template.

Abstract: Real time electronic sequencing methods, devices, and systems are described. Arrays of nanoscale electronic elements comprising capacitive devices with one or two electrodes, or arrays of nanoFET devices are used to provide sequence information about a template nucleic acid in a polymerase-template complex bound proximate to the nanoscale electronic elements or to the substrate proximate to the nanoscale electronic element. A sequencing reaction mixture comprising nucleotide analogs having impedance labels, capacitive labels, or conductivity labels is introduced to the array of nanoscale electronic elements comprising capacitive devices or nanoFETs under conditions of polymerase mediated nucleic acid synthesis. The time sequence of incorporation of nucleotide analogs is determined by identifying the types of labels of the nucleotide analogs that are incorporated into the growing strand using measured impedance, conductivity, or capacitance.

Abstract: Multi-biotinylated reactants are provided which can be used in divalent complexes for various applications such as colocalization, labeling, immobilization, and purification. Methods for constructing, purifying, and using the bis-biotinylated reactants are also provided. In certain embodiments, two bis-biotinylated reactants are bound to a single streptavidin tetramer to provide a complex having a 1:1 stoichiometry with respect to the bis-biotinylated reactants.

Abstract: Multi-biotinylated reactants are provided which can be used in divalent complexes for various applications such as colocalization, labeling, immobilization, and purification. Methods for constructing, purifying, and using the bis-biotinylated reactants are also provided. In certain embodiments, two bis-biotinylated reactants are bound to a single streptavidin tetramer to provide a complex having a 1:1 stoichiometry with respect to the bis-biotinylated reactants.

Abstract: Provided are compositions comprising recombinant polymerases that include amino acid substitutions, insertions, deletions, and/or exogenous features that confer modified properties upon the polymerase for sequencing RNA or RNA/DNA templates. Polymerases that topologically encircle the template nucleic acid are provided. Also provided are methods of using such polymerases to make a DNA or to sequence a template comprising RNA.

Abstract: Compositions, kits, methods and systems for single molecule nucleotide sequencing comprising producing polymerase reactions having lithium that control the median pulse width for incorporated nucleotides are disclosed. The levels of lithium are used to control pulse width while allowing other sequencing parameters to remain within a desirable range.

Abstract: Methods, Compositions, and Systems are provided for nucleic acid sequencing where the sequential incorporation of nucleotides uses two distinct chemical steps. A plurality of nucleotide analogs, each having a labeled leaving group at its 3? hydroxyl can be sequentially added to a growing strand in the presence of a selective cleaving activity that cleaves the 3? hydroxyl leaving group preferentially after it has been incorporated. The selective cleaving agent can comprise an exonuclease activity, and the exonuclease activity can be a polymerase-associated exonuclease activity. Nucleotide analogs having labels on both a cleavable polyphosphate portion and on a 3? hydroxyl leaving group can provide signals characteristic of nucleotide analog incorporation. Systems having illumination optics, collection optics, and substrates observe signals from the labels as they are being incorporated into a growing nucleic acid strand, allowing for the sequencing of template nucleic acids.

Abstract: Real time electronic sequencing methods, devices, and systems are described. Arrays of nanoFET devices are used to provide sequence information about a template nucleic acid in a polymerase-template complex bound to the nanoFET. A sequencing reaction mixture comprising nucleotide analogs having conductivity labels is introduced to the array of nanoscale electronic elements comprising nanoFETs under conditions of polymerase mediated nucleic acid synthesis. The polymerase enzyme template complex is attached to the gate of the nanoFET in an orientation whereby the nucleotide exit region of the polymerase enzyme is directed toward the gate of the nanoFET. Methods for producing nanoFET arrays are provided.

Abstract: Methods, Compositions, and Systems are provided for nucleic acid sequencing where the sequential incorporation of nucleotides uses two distinct chemical steps. A plurality of nucleotide analogs, each having a labeled leaving group at its 3? hydroxyl can be sequentially added to a growing strand in the presence of a selective cleaving activity that cleaves the 3? hydroxyl leaving group preferentially after it has been incorporated. The selective cleaving agent can comprise an exonuclease activity, and the exonuclease activity can be a polymerase-associated exonuclease activity. Nucleotide analogs having labels on both a cleavable polyphosphate portion and on a 3? hydroxyl leaving group can provide signals characteristic of nucleotide analog incorporation. Systems having illumination optics, collection optics, and substrates observe signals from the labels as they are being incorporated into a growing nucleic acid strand, allowing for the sequencing of template nucleic acids.

Abstract: Multimeric protected fluorescent reagents and their methods of synthesis are provided. The reagents are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The reagents contain fluorescent dye elements, that allow the compounds to be detected with high sensitivity at desirable wavelengths, binding elements, that allow the compounds to be recognized specifically by target biomolecules, and protective shield elements, that decrease undesirable contacts between the fluorescent dye elements and the bound target biomolecules and that therefore decrease photodamage of the bound target biomolecules by the fluorescent dye elements. The reagents also contain coupling elements connect monomeric compounds into multimeric forms, thereby increasing brightness.

Abstract: Methods, compositions, and systems are provided for characterization of modified nucleic acids. In certain preferred embodiments, single molecule sequencing methods are provided for identification of modified nucleotides within nucleic acid sequences. Modifications detectable by the methods provided herein include chemically modified bases, enzymatically modified bases, abasic sites, non-natural bases, secondary structures, and agents bound to a template nucleic acid.

Abstract: Provided are compositions comprising recombinant DNA polymerases that include amino acid substitutions, insertions, deletions, and/or exogenous features that confer modified properties upon the polymerase for enhanced single molecule sequencing. Such properties include increased resistance to photodamage, and can also include enhanced metal ion coordination, reduced exonuclease activity, reduced reaction rates at one or more steps of the polymerase kinetic cycle, decreased branching fraction, altered cofactor selectivity, increased yield, increased thermostability, increased accuracy, increased speed, increased readlength, and the like. Also provided are nucleic acids which encode the polymerases with the aforementioned phenotypes, as well as methods of using such polymerases to make a DNA or to sequence a DNA template.