Low Endotoxin Recovery-Masking of Naturally Occurring Endotoxin.

Endotoxins are cell wall components of Gram-negative bacteria. A release of endotoxins into the human blood stream results in an inflammation reaction that can lead to life-threatening conditions like sepsis. Therefore, control for endotoxin contamination of intravenously administered drugs is crucial.

Structural basis of HypK regulating N-terminal acetylation by the NatA complex.

In eukaryotes, N-terminal acetylation is one of the most common protein modifications involved in a wide range of biological processes. Most N-acetyltransferase complexes (NATs) act co-translationally, with the heterodimeric NatA complex modifying the majority of substrate proteins. Here we show that the Huntingtin yeast two-hybrid protein K (HypK) binds tightly to the NatA complex comprising the auxiliary subunit Naa15 and the catalytic subunit Naa10.

Structural insights into a unique Hsp70-Hsp40 interaction in the eukaryotic ribosome-associated complex.

Cotranslational chaperones assist de novo folding of nascent polypeptides, prevent them from aggregating and modulate translation. The ribosome-associated complex (RAC) is unique in that the Hsp40 protein Zuo1 and the atypical Hsp70 chaperone Ssz1 form a stable heterodimer, which acts as a cochaperone for the Hsp70 chaperone Ssb. Here we present the structure of the Chaetomium thermophilum RAC core comprising Ssz1 and the Zuo1 N terminus.

Interaction of the cotranslational Hsp70 Ssb with ribosomal proteins and rRNA depends on its lid domain.

Cotranslational chaperones assist in de novo folding of nascent polypeptides in all organisms. In yeast, the heterodimeric ribosome-associated complex (RAC) forms a unique chaperone triad with the Hsp70 homologue Ssb. We report the X-ray structure of full length Ssb in the ATP-bound open conformation at 2.