Abstract: Modified PKS gene clusters which produce novel polyketides in an efficient system in a host cell or in a cell free extract are described. The novel polyketides result from the incorporation of diketides of the formula
wherein A is a moiety that activates the diketide, and at least one of R1 and R2 is a substituent other than that natively occurring in the diketide normally processed by the modified PKS cluster. The polyketides may also be glycosylated to provide antibiotics.
Type:
Grant
Filed:
May 14, 1999
Date of Patent:
December 31, 2002
Assignees:
Stanford University (Board of Trustees of the Leland Stanford
Junior University), Brown University Research Foundation
Inventors:
Chaitan Khosla, Rembert Pieper, Guanglin Luo, David E. Cane, Camilla Kao
Abstract: Compounds having immunomodulatory activity which are peptide-type compounds, or variants or fragments thereof, including the N-terminal acylated and C-terminal amidated or esterified forms of up to 30 amino acids wherein the peptide-type compound comprises the formula:
(a) R aa76-77 L aa79-84 or
(b) aa84-79 L aa77-76 R
wherein:
aa76 is E or V;
aa77 is D, S or N;
aa79 is R or G;
aa80 is I or N;
aa81 is a small or hydrophobic amino acid
aa82 is R or L;
aa83 is G or R;
aa84 is a small or hydrophobic amino acid;
wherein, in said compounds,
at least one of the amino acids is the D isomer
are used by themselves or in combination with immunosuppressant drugs, to reduce CTL activation, particularly in association with transplantation.
Type:
Grant
Filed:
May 22, 1996
Date of Patent:
August 20, 2002
Assignee:
Stanford University (Board of Trustees of the Leland
Standford Junior University)
Abstract: An acoustic apparatus and method for microscopic imaging and spectroscopy. The apparatus includes a plurality of devices for exciting an object of interest so that acoustic waves are propagated from the object. These devices include lasers, x-ray sources, microwave generators, ultraviolet sources, and electric current generators. The acoustic waves propagated from the object of interest are detected and the object of interest and the acoustic wave detector are moved with respect to each other in a raster scanning pattern. The magnitude of the detected acoustic waves and the corresponding raster pattern of the object are recorded so that a visual image of the object can be obtained. In addition, the frequency of the exciting electromagnetic radiation that excites the object can be varied so that both the absorption spectra and the Raman frequency mode of the object can be determined.