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Since the original SARS-CoV-2 virus emerged from Wuhan, China, in late December 2019, a number of variants have arisen with enhanced infectivity, and some may even be capable of escaping the existing vaccines. Here we describe a rapid automated nucleic acid microarray hybridization and readout in less than 15 min using the Fraunhofer lab-on-a-chip platform for identification of bacterial species and antibiotic resistance. This platform allows a fast adaptation of new biomarkers enabling identification of different genes and gene mutations, such as those seen in the case the SARS-CoV-2 variants.

Most people infected by the SARS-CoV-2 virus which causes COVID-19 disease experience mild or no symptoms. Severe forms of the disease are often marked by a hyper-inflammatory response known as a cytokine storm. Thus, biomarker tests which can identify these patients and place them on the appropriate treatment regime at the earliest possible phase would help to improve outcomes. Here we describe an automated microarray-based immunoassay using the Fraunhofer lab-on-a-chip platform for analysis of C-reactive protein due to its role in the hyper-inflammatory response.

Objective Early diagnosis of atrial fibrillation (AFib) is a priority for stroke prevention. We sought to test four commercial pulse detection systems (CPDSs) for ability to distinguish AFib from normal sinus rhythm using a published algorithm (Zhou et al., PLoS One 2015;10:e0136544), compared with visual diagnosis by electrocardiogram inspection. Methods BAYathlon was a prospective, non-interventional, single-centre study. Adult cardiology patients with documented AFib or sinus rhythm who were due to have a routine 5-min electrocardiogram were randomized to undergo a parallel 5-min pulse assessment with a Polar V800, eMotion Faros 360, TomTom heart rate monitor, or Adidas miCoach Smart Run. Results 144 patients (73 with AFib, 71 with sinus rhythm (based on electrocardiograms); median age: 73 years; 53.5% male) were analysed. Algorithm sensitivities (primary endpoint) and specificities for AFib when applied to CPDS recordings were 93.3% and 94.1% with the Polar V800, 90.0% and 84.2% with the eMotion Faros 360, and 0% and 100% with the other CPDSs (analysis period: 127 heart rate signals + 2 min). When applied to routine electrocardiograms, the algorithm correctly detected AFib in 71/73 patients. Different analysis periods (127 heart rate signals +1 or 3 min) only slightly changed the sensitivities with the Polar V800 and eMotion Faros 360 and had no effect on the sensitivities with the other CPDSs. Conclusion AFib screening using the applied algorithm is feasible with the Polar V800 and eMotion Faros 360 (which provide RR interval data) but not with the other CPDSs (which provide pre-processed heart rate time series). ClinicalTrials.gov identifier: NCT02875106

Diabetic foot ulcer (DFU) is a major complication of diabetes with high morbidity and mortality rates. The pathogenesis of DFUs is governed by a complex milieu of environmental and host factors. The empirical treatment is initially based on wound severity since culturing and profiling the antibiotic sensitivity of wound-associated microbes is time-consuming. Hence, a thorough and rapid analysis of the microbial landscape is a major requirement toward devising evidence-based interventions. Toward this, 122 wound (100 diabetic and 22 nondiabetic) samples were sampled for their bacterial community structure using both culture-based and next-generation 16S rRNA-based metagenomics approach. Both the approaches showed that the Gram-negative microbes were more abundant in the wound microbiome. The core microbiome consisted of bacterial genera, including Alcaligenes, Pseudomonas, Burkholderia, and Corynebacterium in decreasing order of average relative abundance. Despite the heterogenous nature and extensive sharing of microbes, an inherent community structure was apparent, as revealed by a cluster analysis based on Euclidean distances. Facultative anaerobes (26.5%) were predominant in Wagner grade 5, while strict anaerobes were abundant in Wagner grade 1 (26%). A nonmetric dimensional scaling analysis could not clearly discriminate samples based on HbA1c levels. Sequencing approach revealed the presence of major culturable species even in samples with no bacterial growth in culture-based approach. Our study indicates that (i) the composition of core microbial community varies with wound severity, (ii) polymicrobial species distribution is individual specific, and (iii) antibiotic susceptibility varies with individuals. Our study suggests the need to evolve better-personalized care for better wound management therapies. IMPORTANCE Chronic nonhealing diabetic foot ulcers (DFUs) are a serious complication of diabetes and are further exacerbated by bacterial colonization. The microbial burden in the wound of each individual displays diverse morphological and physiological characteristics with unique patterns of host-pathogen interactions, antibiotic resistance, and virulence. Treatment involves empirical decisions until definitive results on the causative wound pathogens and their antibiotic susceptibility profiles are available. Hence, there is a need for rapid and accurate detection of these polymicrobial communities for effective wound management. Deciphering microbial communities will aid clinicians to tailor their treatment specifically to the microbes prevalent in the DFU at the time of assessment. This may reduce DFUs associated morbidity and mortality while impeding the rise of multidrug-resistant microbes.

Schon heute erproben Wissenschaft und Landwirtschaft, was spätestens im Jahr 2046 zum Standard werden dürfte: Künstliche Intelligenz überwacht die Tierbestände und schlägt bei drohenden gesundheitlichen Problemen Alarm.

Lab-on-a-chip assays allow rapid analysis of one or more molecular analytes on an automated user-friendly platform. Here we describe a fully automated assay and readout for measurement of vitamin D levels in less than 15 min using the Fraunhofer in vitro diagnostics platform. Vitamin D (25-hydroxyvitamin D

Lab-on-a-chip assays allow rapid analysis of one or more molecular analytes on an automated user-friendly platform. Here we describe a fully automated assay and readout for measurement of vitamin D levels in less than 15 min using the Fraunhofer in vitro diagnostics platform. Vitamin D (25-hydroxyvitamin D3 [25(OH)D3]) dilution series in buffer were successfully tested down to 2 ng/mL. This could be applied in the future as an inexpensive point-of-care analysis for patients suffering from a variety of conditions marked by vitamin D deficiencies.

Rapid identification of specific TEM-type β-lactamase genes in bacterial infections is important for determining appropriate clinical treatment. We report here the design and initial testing of a molecular diagnostic assay capable of amplifying a large segment of the blaTEM gene, as well as detecting widely spaced extended-spectrum β-lactamase (ESBL) mutations and inhibitor-resistant TEM (IRT) mutations (eg, clavulanic acid resistance). Single-stranded DNA is generated using linear-after-the-exponential PCR (LATE-PCR) and is analyzed at the endpoint, using a set of four fluorescently labeled and four quencher-labeled probes in a single closed tube. These lights-on/lights-off probes work in concert to generate sequence-specific fluorescence contours over a temperature range from 25°C to 75°C. Mutant sequences from synthetic TEM gene variants and from TEM gene variants in bacterial strains generated large increases in fluorescent signal relative to that from the reference sequence for TEM-1. Clinical use of this convenient, single-closed-tube assay would make it possible to rapidly distinguish ESBL from non-ESBL variants and thereby to begin early treatment with suitable antibiotics.

Lab-on-a-chip assays allow rapid identification of multiple parameters on an automated user-friendly platform. Here we describe a fully automated multiplex immunoassay and readout in less than 15 min using the Fraunhofer in vitro diagnostics (ivD) platform to enable inexpensive point-of-care profiling of sera or a single drop of blood from patients with various diseases such as psychiatric disorders.

We analyzed the tear film proteome of patients with dry eye (DE), meibomian gland dysfunction (MGD), and normal volunteers (CT). Tear samples were collected from 70 individuals. Of these, 37 samples were analyzed using spectral-counting-based LC-MS/MS label-free quantitation, and 33 samples were evaluated in the validation of candidate biomarkers employing customized antibody microarray assays. Comparative analysis of tear protein profiles revealed differences in the expression levels of 26 proteins, including protein S100A6, annexin A1, cystatin-S, thioredoxin, phospholipase A2, antileukoproteinase, and lactoperoxidase. Antibody microarray validation of CST4, S100A6, and MMP9 confirmed the accuracy of previously reported ELISA assays, with an area under ROC curve (AUC) of 87.5%. Clinical endpoint analysis showed a good correlation between biomarker concentrations and clinical parameters. In conclusion, different sets of proteins differentiate between the groups. Apolipoprotein D, S100A6, S100A8, and ceruloplasmin discriminate best between the DE and CT groups. The differences between antileukoproteinase, phospholipase A2, and lactoperoxidase levels allow the distinction between MGD and DE, and the changes in the levels of annexin A1, clusterin, and alpha-1-acid glycoprotein 1, between MGD and CT groups. The functional network analysis revealed the main biological processes that should be examined to identify new candidate biomarkers and therapeutic targets.

Lab-on-a-chip multiplex assays allow a rapid identification of multiple parameters in an automated manner. Here we describe a lab-based preparation followed by a rapid and fully automated DNA microarray hybridization and readout in less than 10 min using the Fraunhofer in vitro diagnostics (ivD) platform to enable rapid identification of bacterial species and detection of antibiotic resistance. The use of DNA microarrays allows a fast adaptation of new biomarkers enabling the identification of different genes as well as single-nucleotide-polymorphisms (SNPs) within these genes. In this protocol we describe a DNA microarray developed for identification of Staphylococcus aureus and the mecA resistance gene.

Lab-on-a-chip multiplex assays allow a rapid identification of multiple parameters in an automated manner. Here we describe a lab-based preparation followed by a rapid and fully automated DNA microarray hybridization and readout in less than 10 min using the Fraunhofer in vitro diagnostics (ivD) platform to enable rapid identification of bacterial species and detection of antibiotic resistance. The use of DNA microarrays allows a fast adaptation of new biomarkers enabling the identification of different genes as well as single-nucleotide-polymorphisms (SNPs) within these genes. In this protocol we describe a DNA microarray developed for identification of Staphylococcus aureus and the mecA resistance gene.

Klebsiella pneumoniae carbapenemases (KPCs) are considered a serious threat to antibiotic therapy, as they confer resistance to carbapenems, which are used to treat extended-spectrum beta-lactamase (ESBL)-producing bacteria. Here, we describe the development and evaluation of a DNA microarray for the detection and genotyping of KPC genes ( bla KPC ) within a 5-h period. To test the whole assay procedure (DNA extraction plus a DNA microarray assay) directly from clinical specimens, we compared two commercial DNA extraction kits (the QIAprep Spin miniprep kit [Qiagen] and the urine bacterial DNA isolation kit [Norgen]) for the direct DNA extraction from urine samples (dilution series spiked in human urine). Reliable single nucleotide polymorphism (SNP) typing was demonstrated using 1 × 10 5 CFU/ml urine for Escherichia coli (Qiagen and Norgen) and 80 CFU/ml urine, on average, for K. pneumoniae (Norgen). This study presents, for the first time, the combination of a new KPC microarray with commercial sample preparation for detecting and genotyping microbial pathogens directly from clinical specimens; this paves the way toward tests providing epidemiological and diagnostic data, enabling better antimicrobial stewardship.

The penta-subunit retromer complex of yeast mediates selective retrieval of membrane proteins from the prevacuolar endosome to the trans Golgi network. In this study, we set out to generate a panel of vps35 dominant-negative mutants that disrupt retromer-mediated cargo sorting. Mapping of the mutations revealed two types of alterations leading to dominant-negative behavior of the 944-amino acid protein: (i) mutations at or near the R(98) residue or (ii) C-terminal truncations exemplified by a nonsense mutation at codon 733. Both could be suppressed by overexpression of wild-type Vps35p, suggesting that these dominant-negative mutants compete for interactions with other retromer subunits. Interestingly, Vps35-R(98)W expression destabilized Vps26p while having no effect on Vps29p stability, while Vps35-Q(733)* expression affected Vps29p stability but had no effect on Vps26p. Measurement of Vps35/Vps26 and Vps35/Vps29 pairwise associations by coimmunoprecipitation in the presence or absence of other retromer subunits indicated that the R(98) residue, which is part of a conserved PRLYL motif, is critical for Vps35p binding to Vps26p, while both R(98) and residues 733-944 are needed for efficient binding to Vps29p.

At least two transcription factors, aTFB and aTFA, are required for accurate and faithful in vitro transcription of homologous templates in cell-free extracts from the methanogenic Archaeon Methanococcus thermolithotrophicus. We have recently shown that the function of aTFB can be replaced by eucaryal TATA-binding proteins. Here we demonstrate using template commitment experiments that promoter recognition in an Archaeon is mediated by transcription factors. The archaeal TATA box was identified as recognition site for binding of aTFB by gel shift analyses. aTFB binds also to the TATA box of adenovirus 2 major late promoter suggesting homology of eucaryal and archaeal TATA boxes. Our analyses provide evidence for a common molecular mechanism of transcription initiation by eucaryal RNA polymerases and archaeal RNA polymerase. They indicate also an evolutionary homology for aTFB and TBP.

Human fetuin-A (alpha 2 -Heremans Schmid glycoprotein) has been identified as the most potent circulating inhibitor of vascular and soft-tissue calcification. We aimed to investigate the relationship between the serum fetuin-A level and the progression of aortic valve calcification (AVC) assessed by retrospectively ECG-gated Multislice Spiral Computed Tomography (MSCT) in patients with calcific aortic valve disease. A prospective study in 77 non-dialyzed patients (mean age 70 ± 8 years) with echocardiographically proven aortic valve disease was performed. In all patients serum fetuin-A levels were measured by nephelometry (BNII, Dade Behring Holding, Liederbach, Germany) using a polyclonal rabbit anti-human antibody against fetuin-A. For quantification of AVC all patients underwent 16-slice MSCT (Sensation 16, Siemens, Forchheim, Germany with scan parameters as follows: 420ms tube rotation time, 12× 0.75mm collimation, tube voltage 120KV). After a mean follow-up of 12.6 ± 1.4 months a second non-enhanced MSCT examination for quantification of AVC was performed. Images were reconstructed at 60% of the RR interval. AVC was assessed using Agatston AVC score. In multifactorial analysis of covariance including fetuin-A levels, baseline AVC score, the covariables sex, age, body mass index, C-reactive protein, glomerular filtration rate, serum lipids, diabetes, smoking status and hypertension, only fetuin-A levels revealed a significant effect on the progression of AVC (p 10% (n=48, 62%) had lower fetuin-A serum levels at baseline than non-progressors (n=29, 38%; 0.66±0.13g/L versus 0.82±0.11 g/L, p

In this paper we present a novel highly sensitive detection sy stem for diagnostic applications. The system is designed to meet the needs of medical diagnostics for reliable measurements of pathogens and biomarkers in the low concentration regime. It consists of a confocal detection unit, micro-structured sampling cells, and a “Virtual lab” analysis software. The detection unit works with laser induced fluorescence and is designed to provide accurate and highly sensitive measurement at the single molecule level. Various sampling cells are micro-structured in glass, silicon or polymers to enable measurements under flow and nonflow conditions. Sampling volume is below one microliter. The „“Virtual lab” software analyzes the light intensity online according to the patent pending “Accurate Stochastic Fluorescence Spectroscopy” (ASFS) developed by FluIT Biosystems GmbH. Tools for simulation and experiment optimization are included as well. Experimental results for various applications with relevance for in vitro diagnostics will be presented.

The interdisciplinary project IMIKRID targets the “proof of concept” of a novel technological platform for thedevelopment of customised complete diagnostic systems of ultra high sensitivity for in-vitro diagnostics. For thispurpose, an integrated microfluidic diagnostic platform is developed and its application concerning diagnostic problemsin the area of oncology and cardiovascular diseases as well as in environmental applications will be demonstrated.Keywords: microfluidics, ultra high sensitivity, diagnostics, monitoring, oncology, cardiovascular deseases, completesystem, nanotechnology1. INTRODUCTIONThe centralized and sophisticated bioanalytical systems are representing delays in solving problems in emergencysituations where the rapid diagnostic of diseases, food quality control or environmental pollution monitoring are issues ofcritical concern. There is a high demand of the society for low-cost, user-friendly and accurate bioanalytical systems as the most adequatetools to solve the above problems efficiently and faster. These bioanalytical systems respond selectively to a specificspecies via a suitable combination of a biological or a chemical recognition system and a physical-chemical transducer.They have attracted considerable attention recently as potential successors to a wide range of analytical techniques. Therealization that a large market may exist in disposable and user-friendly bioanalytical devices for use in health care,industry and the environment, has resulted in a large rese arch effort aimed at development of their potential. These simple biosensing systems promise several distinct advantages to the health-care and other sectors overconventional analytical techniques. They may be designed as inexpensive, disposable and portable devices requiringlittle or no expertise for their use. They allow the quantitative detection of specific species in complex samples withoutthe need for sample processing or purification. These features provide the opportunity for decentralization of sampleanalysis from the hospital’s analytical laboratory to the doctor’s office and the patient’s bedside, and for self-testing inthe home. The volume of sample required can be reduced from mL to few µL or less due to microfabricationtechnologies. Results may be obtained immediately in situations where delay may be critical. These user friendlybiosystems may be implanted to allow continuous monitoring of patient status. Multi-analytical devices allowquantification of several species simultaneously. These simple bioanalytical systems employ direct coupling of an immobilized biological component, such as DNA,antibodies, enzymes etc that are responsible for the specific recognition of the species of interest, to a transducer system,which detects the biological or chemical recognition event and converts it into a quantifiable electrical signal. Thebiological moiety may be a macromolecule such as an enzyme , antibody, receptor or oligonuc leotide; or a more complexstructure such as an organelle, a whole cell, or even a tissue slice. The transducer is generally dictated by the nature ofthe biological response, and may be electrical, electrochemical, thermo metric, optical or piezoelectric. Progress in simple bioanalytical systems development has been varied in the different arms of the field in the last decade.For traditional bioanalytical systems such as glucose sensors, examples of which reached commercialization in the late1980s, steady improvements in its stability have been achieved. On the other hand, affinity bioanalytical systems havemade major progress towards commercialization. The introduction of laboratory affinity-based bioanalytical systems haspermitted rapid functional analysis of biomolecular interactions in real time. New ways to miniaturize these bioanalyticalsystems and to control their interfaces down to the molecular level have been introduced (the bioelectronics approach),and high-throughput screening based on various signal transduction principles has become of increasing importance.

This paper presents a stochastic theory for the interpretation of photon counting histograms in fluorescence fluctuation spectroscopy (FFS). New concepts of an effective volume and a single molecule probability distribution are introduced to characterize a molecular species. Whereas the effective volume corresponds to the visibility of a molecular species in a given confocal setup, the single molecule probability distribution gives the signal measured for a single visible molecule. Specific properties of the effective volume and the single molecule probability distribution are discussed. Advantages arise for the high precision measurements of concentrations, mixtures, and binding constants especially for complex molecular environment, e.g. in flow systems and cell compartments.

Our understanding of the mechanism of RNA biosynthesis in archaebacteria is limited, due in part to the inability of purified RNA polymerases to transcribe purified genes accurately in vitro. In the present study, we show that cell extracts of Methanococcus vannielii and Methanococcus thermolithotrophicus purified by gradient centrifugation synthesize a distinct transcript from templates harboring a cloned homologous tRNA(Val) and tRNA(Arg) gene. The in vitro transcripts initiate with GTP at the same sites as in Methanococcus cells. About 60% of the sequence of the in vitro RNA products was analyzed by dideoxyterminated primer extension and found to be identical with that of the precursors of tRNA(Val) and tRNA(Arg). This finding indicates that this RNA polymerase fraction both initiates and terminates transcription faithfully in vitro. After purification of a cell-free extract (S-100) of M. thermolithotrophicus by phosphocellulose chromatography, the endogenous RNA polymerase has lost its ability to transcribe the tRNA(Val) gene accurately. The activity directing specific expression of this template was reconstituted by the addition of a protein-fraction devoid of RNA polymerase activity. Thus, a transcription factor appears to be required for accurate cell-free expression of tRNA genes from M. vannielii.

The retromer protein complex assists in recycling selected integral membrane proteins from endosomes to the trans Golgi network. One protein subcomplex (Vps35p, Vps26p and Vps29p) combines with a second (Vps17p and Vps5p) to form a coat involved in sorting and budding of endosomal vesicles. Yeast Vps35p (yVps35) exhibits similarity to human Vps35 (hVps35), especially in a completely conserved PRLYL motif contained within an amino-terminal domain. Companion studies indicate that an R(98)W mutation in yVps35 causes defective retromer assembly in Saccharomyces cerevisiae. Herein, we find that the expression of hVps35 in yeast confers dominant-negative vacuolar proenzyme secretion and defective secretory proprotein processing. The mutant phenotype appears to be driven by hVps35 competing with endogenous yVps35, becoming incorporated into defective retromer complexes and causing proteasomal degradation of endogenous Vps26 and Vps29. Increased expression of yVps35 displaces some hVps35 to a 100 000 x g supernatant and suppresses the dominant-negative phenotype. Remarkably, mutation of the conserved R(107)W of hVps35 displaces some of the protein to the 100 000 x g supernatant, slows protein turnover and restores stability of Vps26p and Vps29p and completely abrogates dominant-negative trafficking behavior. We show that hVps35 coprecipitates Vps26, whereas the R(107)W mutant does not. In pancreatic beta cells, the R(107)W mutant shifts hVps35 from peripheral endosomes to a juxtanuclear compartment, affecting both mannose phosphate receptors and insulin. These data underscore importance of the Vps35 PRLYL motif in retromer subcomplex interactions and function.

This paper presents an experimental and numerical investigation into film cooling performance over a flat plate. As previous studies have shown, the flow situation at the entry-side of the cooling hole shows a notable effect on film cooling performance. The present investigation takes this into account feeding the cooling holes from an internal cooling channel and not from a stagnant plenum. High resolution heat transfer coefficient and adiabatic film cooling effectiveness distributions received from transient liquid crystal experiments are presented. The Reynolds numbers of the hot gas channel and the coolant crossflow feeding the holes are varied. Furthermore, the effects of 45° angled ribs, introduced into the cooling channel, are investigated. The experiments are performed at constant blowing, momentum and pressure ratios. Numerical calculations of the adiabatic film cooling effectiveness for selected configurations using FLUENT are presented. Comparison reveals the influence of coolant channel Reynolds number and the introduced ribs on the cooling hole flow pattern leading to a changed film cooling performance.Copyright © 2007 by ASME

Calcific aortic valve disease is present in more than 25% of patients65 years of age and is associated with a 50% increased risk of cardiovascular events. The clinical significance of aortic valve calcification detected incidentally by radiologic examinations, especially on CT scans of the chest, was unknown. Concerning the multifactorial pathogenesis of aortic valve calcification, recent data indicate that, besides other factors, also the regulators of calcification play a key role in the disease process.This study aims to give an overview of the prevalence and clinical significance of incidentally detected aortic valve calcifications. Moreover, the role calcification inhibitors in the pathogenesis of aortic valve calcification is discussed.

Transesophageal echocardiography (TEE) has opened a new window to the heart. Its success rate is impressive. In less than 2 decades it has become an integral part of pediatric and adult cardiology as well as cardiac surgery and anesthesiology. The range of indications has broadened since its introduction almost 20 years ago. The combination of unique morphological and hemodynamic information of exceptional diagnostic quality and the possibility to use this diagnostic method as a bedside tool in the intensive care unit and the operating room guarantee that this diagnostic modality will maintain its firm place in the diagnostic armamentarium of cardiologists and anesthesiologists, besides novel and emerging imaging modalities such as cardiac magnetic resonance imaging (MRI) and multislice computed tomography (MSCT). Technical improvements in transducer technology and the development of miniaturized matrix transducers may, in the near future, allow real-time three-dimensional viewing of the heart even from the esophagus. It is anticipated that this will further increase the diagnostic potential of the technique and its importance for guiding of therapeutic procedures.

This work focuses on the development of an online programmable microfluidic bioprocessing unit (BioModule) using digital logic microelectrodes for rapid pipelined selection and transfer of DNA molecules and other charged biopolymers. The design and construction technique for this hybrid programmable biopolymer processing device is presented along with the first proof of principle functionality. The electronically controlled collection, separation and channel transfer of the biomolecules is monitored by a sensitive fluorescence setup. This hybrid reconfigurable architecture couples electronic and biomolecular information processing via a single module combination of fluidics and electronics and opens new fields of applications not only in DNA computing and molecular diagnostics but also in applications of combinatorial chemistry and lab-on-a-chip biotechnology to the drug discovery process. Fundamentals of the design and silicon-PDMS-based construction of these electronic microfluidic devices and their functions are described as well as the experimental results.

This work focuses on the development of an online programmable microfluidic bioprocessing unit (BioModule) using digital logic microelectrodes for rapid pipelined selection and transfer of deoxyribonucleic acid (DNA) molecules and other charged biopolymers. The design and construction technique for this hybrid programmable biopolymer processing device is presented along with the first proof of principle functionality. The electronically controlled collection, separation and channel transfer of the biomolecules is monitored by a sensitive fluorescence set-up. This hybrid reconfigurable architecture couples electronic and biomolecular information processing via a single module combination of fluidics and electronics and opens new fields of applications not only in DNA computing and molecular diagnostics but also in applications of combinatorial chemistry and lab-on-a-chip biotechnology to the drug discovery process. Fundamentals of the design and silicon–polydimethylsiloxane (PDMS)-based construction of these electronic microfluidic devices and their functions are described as well as the experimental results.

In the growing field of microsystems for analysis systems there is a major need of simple and stable micro devices to manipulate and switch fluid currents. Common devices use movable parts like membranes to control the flow through a given micropart. The main disadvantages of these microvalves are their liability to dirt, their cross sensitivity against external pressure differences and the difficulties to introduce the power to move the membranes. To circumvent the use of movable parts, different technical principles like the electroosmotic flow were introduced in the microworld. Microdevices using these technical systems often suffer from principle limitations too.

TATA boxes are common structural features of eucaryal class II and archaeal promoters. In addition, a gene encoding a polypeptide with sequence similarity to eucaryal TATA-binding protein (TBP) has recently been detected in Archaea, but its relationship to the archaeal transcription factors A (aTFA) and B (aTFB) was unclear. Here, we demonstrate that yeast and human TBP can substitute for aTFB in a Methanococcus-derived archaeal cell-free transcription system. Template-commitment studies show that eucaryal TBP is stably sequestered at the archaeal promoter and that this interaction is further stabilized in combination with aTFA. Binding studies revealed that recognition of an archaeal promoter by TBP involves specific binding to the TATA box. These findings demonstrate a common function of TBP and aTFB and imply a common evolutionary origin of eucaryal and archaeal transcriptional machinery.