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The 8 th Chemical Protein Synthesis meeting took place in Berlin in June 2019, covering broad topics in protein chemistry, ranging from synthetic methodology to applications in medicine and biomaterials. The meeting was also the culmination of the Priority Program SPP1623 on "Chemoselective Reactions for the Synthesis and Application of Functional Proteins" funded by the German Science Foundation (DFG) from 2012 to 2018. We present highlights from presentations at the forefront of the field, grouped into broad themes that illustrate how the field of protein chemistry is looking ahead to new discoveries and applications., (Copyright © 2019.)

Synchrotron radiation circular dichroism (SRCD) is a rapidly growing technique for structure analysis of proteins and other chiral biomaterials. UV-CD12 is a high-flux SRCD beamline installed at the ANKA synchrotron, to which it had been transferred after the closure of the SRS Daresbury. The beamline covers an extended vacuum-UV to near-UV spectral range and has been open for users since October 2011. The current end-station allows for temperature-controlled steady-state SRCD spectroscopy, including routine automated thermal scans of microlitre volumes of water-soluble proteins down to 170 nm. It offers an excellent signal-to-noise ratio over the whole accessible spectral range. The technique of oriented circular dichroism (OCD) was recently implemented for determining the membrane alignment of α-helical peptides and proteins in macroscopically oriented lipid bilayers as mimics of cellular membranes. It offers improved spectral quality <200 nm compared with an OCD setup adapted to a bench-top instrument, and accelerated data collection by a factor of ∼3. In addition, it permits investigations of low hydrated protein films down to 130 nm using a rotatable sample cell that avoids linear dichroism artifacts.

The introduction of synchrotron radiation sources almost four decades ago has led to a revolutionary change in the way that diffraction data from macromolecular crystals are being collected. Here a brief history of the development of methodologies that took advantage of the availability of synchrotron sources are presented, and some personal experiences with the utilization of synchrotrons in the early days are recalled.

The EMBL Hamburg Outstation currently operates five synchrotron beamlines for protein crystallography. The strongest of these beamlines is the fixed-energy beamline BW7B which receives about half of the radiation (1.5 mrad) from a 56 pole wiggler located at the DORIS III storage ring at the German synchrotron facility DESY. Over the last years this beamline has been upgraded and equipped with a fully automated crystallographic end-station and a robotic sample changer. The current set-up allows for remote operation, controlled from the user's area, of sample mounting, centering and data collection of pre-frozen crystals mounted in Hampton-type cryovials on magnetic caps. New software and intuitive graphical user interfaces have been developed that control the complete beamline set-up. Furthermore, algorithms for automatic sample centering based on UV fluorescence are being developed and combined with strategy programs in order to further automate the collection of entire diffraction data sets.

A fully automated system for screening protein crystals for X-ray diffraction analysis has been designed and is being installed on the beamline BW6 at DORIS in Hamburg, Germany. The system includes robotic mounting of flash-frozen crystals from a storage dewar, centering and alignment of the sample both by optical and X-ray (scattering and fluorescence) techniques, assessment of the diffraction quality of the sample, and SAD/MAD or non-conventional diffraction data acquisition with high-throughput data rates. The system covers all experimental steps required for protein x-ray structure analysis and provides a powerful means for structural genomics projects.

More than 500 unrelated patients with neurofibromatosis type 1 (NF1) were screened for mutations in the NF1 gene. For each patient, the whole coding sequence and all splice sites were studied for aberrations, either by the protein truncation test (PTT), temperature-gradient gel electrophoresis (TGGE) of genomic PCR products, or, most often, by direct genomic sequencing (DGS) of all individual exons. A total of 301 sequence variants, including 278 bona fide pathogenic mutations, were identified. As many as 216 or 183 of the genuine mutations, comprising 179 or 161 different ones, can be considered novel when compared to the recent findings of Upadhyaya and Cooper, or to the NNFF mutation database. Mutation-detection efficiencies of the various screening methods were similar: 47.1% for PTT, 53.7% for TGGE, and 54.9% for DGS. Some 224 mutations (80.2%) yielded directly or indirectly premature termination codons. These mutations showed even distribution over the whole gene from exon 1 to exon 47. Of all sequence variants determined in our study, <20% represent C-->T or G-->A transitions within a CpG dinucleotide, and only six different mutations also occur in NF1 pseudogenes, with five being typical C-->T transitions in a CpG. Thus, neither frequent deamination of 5-methylcytosines nor interchromosomal gene conversion may account for the high mutation rate of the NF1 gene. As opposed to the truncating mutations, the 28 (10.1%) missense or single-amino-acid-deletion mutations identified clustered in two distinct regions, the GAP-related domain (GRD) and an upstream gene segment comprising exons 11-17. The latter forms a so-called cysteine/serine-rich domain with three cysteine pairs suggestive of ATP binding, as well as three potential cAMP-dependent protein kinase (PKA) recognition sites obviously phosphorylated by PKA. Coincidence of mutated amino acids and those conserved between human and Drosophila strongly suggest significant functional relevance of this region, with major roles played by exons 12a and 15 and part of exon 16.

The Munich Information Center for Protein Sequences (MIPS-GSF), Martinsried near Munich, Germany, develops and maintains genome oriented databases. It is commonplace that the amount of sequence data available increases rapidly, but not the capacity of qualified manual annotation at the sequence databases. Therefore, our strategy aims to cope with the data stream by the comprehensive application of analysis tools to sequences of complete genomes, the systematic classification of protein sequences and the active support of sequence analysis and functional genomics projects. This report describes the systematic and up-to-date analysis of genomes (PEDANT), a comprehensive database of the yeast genome (MYGD), a database reflecting the progress in sequencing the Arabidopsis thaliana genome (MATD), the database of assembled, annotated human EST clusters (MEST), and the collection of protein sequence data within the framework of the PIR-International Protein Sequence Database (described elsewhere in this volume). MIPS provides access through its WWW server (http://www.mips.biochem.mpg.de) to a spectrum of generic databases, including the above mentioned as well as a database of protein families (PROTFAM), the MITOP database, and the all-against-all FASTA database.

Patent law is intended to provide protection for new and inventive achievements in technology. Technical progress is considered to be the purpose and aim of patent law. The main objective of patent law is to protect patentable results according to the latest state of science and research. It is most important to encourage the inventor to completely publish his knowledge. As a reward for this the inventor is granted a right of exclusion which is limited in time: the patent. It is not the purpose of patent law to enrich mere theory but to create industrially applicable knowledge for the public. This contribution deals with important problems to be considered by inventors in the patenting of inventions in the field of biology and chemistry. Such questions are related particularly to the accessibility of inventions and discoveries to patent protection, the various kinds (categories) of patents, the requirement of novelty, complete disclosure of the invention, patentability of DNA sequences and proteins, as well as inventive step.