NEWS OF THE WEEK PROTEOMICS
YEAST CELLS BRIM WITH MACHINERY Thousands of proteins mix and match into hundreds of complexes
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T S CHALLENGING ENOUGH TO
elucidate the structure and function of a single protein in a cell, yet proteomics researchers are wielding a bevy of high-throughput analytic tools and computational methods that provide group snapshots of the thousands of proteins that simultaneously carry out life's activities.
SPOT ON Plates with purified protein (within circles) from yeast cells are destined to undergo mass spectrometric analysis. A team of 32 academic and industry scientists in Germany has now shown how 2,760 proteins in budding yeast cells assemble into 491 complexes, 257 of which had not been identified before (Nature, published online Jan. 22, dx.doi. org/10.1038/nature04532). "It's a bit like human society," suggests Gitte Neubauer, one of the researchers from a Heidelberg subsidiary of the drug discovery company Cellzome. "People come together in different groupings to fill particular functions," she says. For their vast survey of yeast proteins, Neubauer and her Cellzome colleagues teamed with researchers at the Heidelberg unit of the EuropeWWW.CEN-0NLINE.ORG
an Molecular Biology Laboratory. D Nucleolus D Cytoplasm B Nucteus T h e researchers were able to extract, purify, and identify 2,760 PROTEIN MACHINES Proteomic analyses distinct proteins using a method reveal that proteins form regular transient known as TAP-MS, short for groupings—big cores and smaller modules—that tandem affinity purification-mass join into even larger complexes. Colors indicate spectrometry. The method allows cellular localization of proteins. each of the nearly 6,500 genes of Saccharomyces cerevisiae cells to be modified so that their associated the cell's machinery. Even with proteins bear hooks for specialized this sizable inventory of protein antibodies used in the extraction complexes, the researchers suspect and purification process. that the study still missed as many as 300 cores. Further analysis of the data indicated how the proteins join into "If we are going to understand complexes that can perform celluhow a cell works, we need to unlar jobs such as generating energy derstand the protein complexes and defense. These complexes are within them," says Anuj Kumar, made up of "cores" involving up to a functional genomics researcher 23 proteins, smaller "modules" of at the University of Michigan. a few proteins, and individual pro"This is a huge step toward that teins that all mix and match into goaT— IVANAMAT0
SPECIALTY
CHEMICALS
Engelhard Spurns BASF's $4.9 Billion Bid
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ngelhard's board announced last week that it has rejected BASF's $4.9 billion hostile takeover bid as inadequate and that it would seek another buyer. BASF shot back saying that its $37-pershare bid is "fair and compelling" and that Engelhard's rejection is not in the best interests of its shareholders. "Our board unanimously determined that BASF's offer is opportunistic and undervalues Engelhard," said Chief Executive Officer Barry W. Perry. In a statement, the company said the board determined that BASF understates the value of synergies between the two
companies and that the offer is below premiums that have been offered for comparable and smaller specialties businesses. The statement also refers to "third parties" that have expressed an interest in a deal with Engelhard. Perry noted that the firm in recent years has divested older, low-margin businesses such as precious-metal fabrication and invested the proceeds into higher margin, high-growth businesses. Perry forecasts growth in key Engelhard markets such as environmental control, which he estimated will jump from 5%-plus annual growth to "lowteens" growth in 2007 with the
advent of new clean air regulations worldwide. He also noted positive growth forecasts in businesses serving energy, health, and cosmetics markets. In 2005, Perry said, the company generated more than $100 million in operating earnings from businesses that are less than five years old. BASF Chairman Jurgen Hambrecht responded that he is committed to purchasing Engelhard. "However, in its response to our tender offer, Engelhard did not provide any information that would prompt us to improve the terms of our current offer," Hambrecht said.-RICKMULLIN
C & E N / J A N U A R Y 3 0 , 2006
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