Europaisches Laboratorium Fur Molekularbiologie (embl)

Carl-zeiss-stiftung

Europaisches Laboratorium Fur Molekularbiologie

Europaisches Laboratorium Fur Molekularbiologic (embl)

Europasches Laboratorium Fur Molekularbiologie (embl)

Europaisches Laboratorium Fur Mokekularbiologie (embl)

Wilhelm Ansorge

Hartmut Voss

Walter Geis

Brian Sproat

Albrecht Kettler

Josef Stegemann

Volker Wilke

Christian Schwager

Konrad Faulstich

Stefan Wiemann

Holger Erfle

Hubert Nasse

The invention relates to 5&prime;-modified nucleotides and to nucleic acids which contain these nucleotides. Processes for incorporating the 5&prime;-modified nucleotides into nucleic acids, and the subsequent site-specific cleavage of the nucleic acids at the 5&prime;-modified monomer building blocks, are also disclosed. These processes can be employed for nucleic acid sequencing, for generating nucleic acid libraries, for detecting mutations, for preparing support-bound nucleic acids and for pharmaceutical purposes.

5&prime;-modified nucleotides and the application thereof in molecular biology and medicine

In the method moving a sample substance by means of a sample feeder ( ) form a sample pickup site to a delivery site ( ) of a sample processor ( ), the invention proposes fitting the sample feeder ( ) with at least one porous material element having a pore size such that the sample substance shall be kept in the liquid phase in the porous material at least during sample pickup by the sample feeder ( ) and during sample delivery to the sample processor ( ).

Sampler transfer

Simultaneous sequencing of nucleic acids

Method for sequencing nucleic acids

Apparatus for carrying out chemical reaction sequences

For the sequencing of nucleic acids by enzymatic extension of an oligonucleotide primer in the presence of a polymerase, the four deoxyribonucleoside triphosphates, one of the four dideoxynucleoside triphosphates and the nucleic acid to be sequenced as template in each of four different preparations, labelling of the nucleic acid fragments which form and which are dependent on the dideoxynucleoside triphosphate used, separation by gel electrophoresis of the preparations containing the fragments and detection of the sequence via the label, at least two of the dideoxynucleoside triphosphates are used in different amounts together in one preparation and the fragments are differentiated by the intensity of the labelling signal of the bands in the gel or in another separation procedure.

Process for sequencing nucleic acids

The invention is directed to a method for performing work on cells of a cell culture which includes microinjecting cells in the cell culture or drawing liquid from an individual cell or withdrawing whole cells with the aid of suction from the cell culture. The system is computer-supported and a marker movable in the image on a monitor is superposed on a television image of the cell culture. The marker is positioned in the television image on the cell to be injected by the operator by means of a relative movement of the marker with respect to the image. The coordinates of the cells marked in this way are stored by the computer which thereafter advances the capillary point automatically to the selected cells and penetrates the latter. Pursuant to a feature of an advantageous embodiment of the invention, the computer guides the penetration movement parallel to the longitudinal axis of the capillary by means of a superposed movement (k) of the object stage and through a superposed movement of the drive for the elevation displacement (z) of the capillary on the micromanipulator.

Method for performing work on cells of a cell culture and apparatus

A method and a device are proposed for the injection of very small amounts of samples into cells (74) with the aid of a microcapillary (10). During the injection, a constant injection pressure of about 0.12 bar, provided by a pressurized cylinder (46) is applied ot the microcapillary (10), which is reduced after the completion of the injection to a holding pressure of 0.02 bar until the next cell (64) is to be injected. A high-pressure (p.sub.1) supplied from another pressurized cylinder (44) serves for blowing out the microcapillary tip (12). A three-way valve (42) permits simple and rapid switching between the various pressure (p.sub.1, p.sub.2 and p.sub.3). Reproducible amounts of sample in the range from 10.sup.-11 ml to 10.sup.-13 ml can be injected reprodicibly, simply and rapidly.

Device for the injection of very small amounts of samples into cells

A method and a device are proposed for the injection of very small amounts of samples into cells (74) with the aid of a microcapillary (10). During the injection, a constant injection pressure of about 0.12 bar, provided by a pressurized cylinder (46) is applied to the microcapillary (10), which is reduced after the completion of the injection to a holding pressure of 0.02 bar until the next cell (64) is to be injected. A high-pressure (p.sub.1) supplied from another pressurized cylinder (44) serves for blowing out the microcapillary tip (12). A three-way valve (42) permits simple and rapid switching between the various pressures (p.sub.1, p.sub.2 and p.sub.3). Reproducible amounts of sample in the range from 10.sup.-11 ml to 10.sup.-13 ml can be injected reproducibly, simply and rapidly.

Process for the injection of very small amounts of samples into cells

A method and apparatus for preparing thin layers, such as thin gel layers useful in electrophoresis, wherein a liquid layer material is introduced to the space defined between two parallel mold surfaces on first and second mold elements. Initially, the mold surfaces overlap each other to a small extent, and liquid is introduced to the space between the surfaces adjacent the leading edge of the top mold element. The mold elements are then shifted with respect to each other while maintaining their parallel relationship, and additional liquid layer-forming material is introduced to the space during the shift. In a preferred embodiment, a third mold element is situated adjacent to and spaced a small distance from the bottom mold element, and liquid material is introduced to the space between the bottom mold elements during shifting of the top mold.

Method for preparing thin layers

Growing community of inventors

Gaiberg, Germany

Wilhelm Ansorge