Einblicke in die Funktionsweise komplexer Transportmaschinerien(S. 696)
Narcis-Adrian Petriman, Benjamin Jauß, Hans-Georg Koch
Compartmentalization is a unifying principle of eukaryotic and prokaryo - tic cells and necessitates specific protein delivery systems that transport proteins from their site of synthesis in the cytosol to their sites of function. Bacteria use a large variety of protein delivery systems in parallel to transport proteins to the cell envelope and into the extracellular environment. The universally conserved Sec translocon and the YidC insertase constitute the two main transport systems in the cytoplasmic membrane of Gram-negative bacteria.
Der Beitrag der Gene beim Parkinson-Syndrom(S. 699)
In the past two decades, a number of genetic causes of Parkinson disease (PD) have been elucidated. This includes both monogenic forms in which a single mutation is sufficient to cause PD and genetic risk factors. The latter only increase the susceptibility for PD and additional, likely environmental hits are necessary to develop the disease. PD genes such as LRRK2 and Parkin often encode proteins involved in mitochondrial function, protein degradation, or response to oxidative stress.
Genetisches Risiko bei der altersabhängigen Makuladegeneration(S. 703)
Bernhard H. F. Weber, Felix Grassmann, Julika Loss, Iris M. Heid
Age-related macular degeneration (AMD) is a frequent cause of blindness influenced by environmental and genetic risk factors. While current knowledge on AMD genetics and its use in diagnostic testing is readily present in press and electronic media, risk quantification is still a challenge when communicating testing results. Here we ask whether and how this information is perceived by the public, specifically in light of the lack of preventive and therapeutic measures of this devastating disease.
Pathobiochemie des Sec61-Komplexes in der ER-Membran(S. 706)
Stefan Schorr, Markus Greiner, Adolfo Cavalié, Richard Zimmermann
In human cells, the endoplasmic reticulum (ER) is central to protein biogenesis and Ca2+ homeostasis. Protein biogenesis requires an aqueous polypeptide-conducting channel in the ER membrane, the heterotrimeric Sec61 complex; the Ca2+ homeostasis involves a steep Ca2+ gradient from ER to cytosol. Therefore, gating of the Sec61 channel is regulated by substrates and allosteric effectors. Several human diseases are linked to Sec61 complex and its effectors and were termed Sec61-channelopathies.
Humane Archaeen: salutogen statt pathogen?(S. 709)
The human body is a complex biotope for thousands of different species of microorganisms. Bacteria, Archaea, viruses, and fungi are part of this microbial community, which influences our body in function and wellbeing. Although archaeal presence has been proven in e. g. mouth, intestinal tract, and on skin, they remain understudied with respect to abundance, diversity, and function in the human microbiome, although they seem to have more beneficial than pathogenic properties.
Rekonstruktion urzeitlicher Proteine(S. 712)
Rainer Merkl, Reinhard Sterner
The characterization of proteins from the early phases of life is interesting but hampered by the lack of macromolecular fossils. This limitation can be overcome by computational methods, which allow for the reconstruction of ancestral proteins based on the sequences of extant homologs. The biochemical analysis of these proteins helps to answer quite different questions, as those related to the environmental conditions in the Precambrian era or the diversification of protein families.
Bildgebende Verfahren zur Darstellung von Biofilmen und Bioaggregaten(S. 715)
Thomas R. Neu, Ute Kuhlicke
Imaging of microbial biofilm systems by means of laser based microscopy experienced significant progress by improvement of established approaches as well as invention of new technologies. The various techniques allow examination of hydrated biofilms and bioaggregates at the meso-, micro-, and nano-scale. Apart from new hardware technology more sophisticated software tools have been developed. Here the major techniques are briefly discussed with respect to their advantages and limitations for imaging biofilm systems.
Proteinvermessung: Präzise Abstandsverteilungen im Nanometerbereich(S. 718)
Julia Cattani, Marta Robotta, Malte Drescher
Long range distance constraints are crucial for investigating structure and dynamics of bio-macromolecules. Exploiting electron paramagnetic resonance spectroscopy in combination with site-directed spin labelling gives access to precise distance distributions in the nanometer range, even for large protein complexes and in complex environments, e. g., in cellula.
Molekularbiologische Methoden zur HLA-Typisierung(S. 721)
Frank Grünebach, Reinhild Klein
The success of allogeneic stem cell transplantation depends upon the degree of human leukocyte antigen (HLA) compatibility between the donor and patient since T-cell responses to foreign HLA molecules can result in aggressive immune responses. The human HLA locus on chromosome 6 is highly polymorphic within the population. Due to the large number of allels, the exact determination of the individual HLA polymorphisms (HLA typing) is a technically challenging task requiring different molecular biological procedures.
Myeloperoxidase – ein neuer Marker zur Erforschung von Entzündungen?(S. 725)
Jörg Flemmig, Anna Leichsenring, Franziska Lange
Neutrophilic granulocytes, the most abundant immune cell type in the blood, are essential for the initiation as well as for the regulation and termination of acute inflammatory reactions. Thereby the enzyme myeloperoxidase (MPO) formed by these cells could be a key player. Thus a newly developed method for the quick purification of neutrophilic granulocytes from blood samples and a subsequent activity staining for MPO is presented which may contribute to a better understanding of the (patho-)physiological role of this enzyme.
Ein neues Verfahren zur Frühdiagnose der Alzheimerschen Demenz(S. 728)
Oliver Bannach, Katja Kühbach, Dieter Willbold
Alzheimer’s disease is a fatal neurodegenerative disorder with limited therapeutic and diagnostic options. Oligomers of the amyloid-β peptide drive disease pathology and consequently represent the most promising biomarker candidate. Here, we present the sFIDA technology which is capable of quantifying single amyloid-β oligomers in body fluids as early biomarker for Alzheimer’s disease.
Chancen und Grenzen der liquid biopsy für die Tumordiagnostik(S. 731)
Steffen Dietz, Anja Riediger, Michael Thomas, Uwe Schirmer, Holger Sültmann
Circulating DNA released from cancerous tissues has been found to harbour tumour-associated alterations and to represent the molecular composition of the tumour. Recent advances in technologies, especially in next-generation sequencing, enable the analysis of low amounts of circulating DNA from body fluids. These “liquid biopsies” allow tumour genotyping and therapy monitoring without invasive procedures and offer the potential for early cancer detection.
Anwendungen & Produkte
Plattenbasiertes Wirkstoffscreening(S. 746)
Katherine Gillis, Julie Clor, Kamala Tyagarajan
Drug-based screening, identification of ‘hit’ compounds, and evaluation of mode of action require the parallel understanding of how the drug modulates critical cellular parameters which eventually lead to cytotoxicity or disrupt cellular proliferation. Given the increased need for assays with high informational content and mechanism-based data, researchers turn to flow cytometry with its potential for quantifiable comparisons between cell populations.
Trends in der Genomeditierung für die industrielle Biotechnologie(S. 788)
Bastian Blombach, Kathrin Castiglione, Thomas Haarmann, Jochen Schmid
Industrial biotechnology relies on the availability of highly efficient enzymes and production strains for the development of economically viable processes. Recent advances in the field of genome editing will greatly speed up the implementation of desired metabolic pathways and their optimization, thereby facilitating fast and cost-effective production strain engineering.