Author
Markus Wyss
Other affiliations: École Polytechnique Fédérale de Lausanne, Hoffmann-La Roche
Bio: Markus Wyss is an academic researcher from DSM. The author has contributed to research in topics: Creatine kinase & Creatine. The author has an hindex of 35, co-authored 62 publications receiving 9254 citations. Previous affiliations of Markus Wyss include École Polytechnique Fédérale de Lausanne & Hoffmann-La Roche.
Topics: Creatine kinase, Creatine, Phytase, Peptide sequence, Aspergillus niger
Papers published on a yearly basis
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TL;DR: A comprehensive survey of the many intriguing facets of creatine (Cr) and creatinine metabolism is presented, encompassing the pathways and regulation of Cr biosynthesis and degradation, species and tissue distribution of the enzymes and metabolites involved, and of the inherent implications for physiology and human pathology.
Abstract: The goal of this review is to present a comprehensive survey of the many intriguing facets of creatine (Cr) and creatinine metabolism, encompassing the pathways and regulation of Cr biosynthesis an...
2,332 citations
1,940 citations
TL;DR: To extend the biochemical characterization of wild-type phytases, the catalytic properties of a series of fungal phytased, as well as Escherichia coli phytase, were determined and phosphate liberation kinetics were studied in vitro.
Abstract: The phosphatases are a diverse class of enzymes. According to one classification, alkaline phosphatases, purple acid phosphatases, high-molecular-weight acid phosphatases, low-molecular-weight acid phosphatases, and protein phosphatases can be distinguished (13). These classes differ in their pH optima, metal ion requirements, substrate specificities, and possibly even reaction mechanisms. The phytases (myo-inositol hexakisphosphate phosphohydrolases; EC 3.1.3.8 and 3.1.3.26) are a subfamily of the high-molecular-weight histidine acid phosphatases. The phytase reaction mechanism is a two-step mechanism which includes a covalent phosphohistidine adduct as an obligatory reaction intermediate (6).
Phytases are found naturally in plants and microorganisms, particularly fungi (for a review see reference 15). They catalyze phosphate monoester hydrolysis of phytic acid (myo-inositol hexakisphosphate), which results in the stepwise formation of myo-inositol pentakis-, tetrakis-, tris-, bis-, and monophosphates, as well as the liberation of inorganic phosphate. Phytic acid is the major storage form of phosphorus in plant seeds and, thus, in seed-based animal feed (for reviews see references 1 and 8). Monogastric animals, such as pigs and poultry, are not able to utilize phytic acid phosphorus, since they have only low levels of phytase activity in their digestive tracts and since phytic acid cannot be resorbed. Therefore, pig and poultry feed commonly is supplemented with either inorganic phosphate or a phytase of fungal origin.
Despite considerable economic interest, only limited data on the catalytic properties of fungal phytases are available. In order to get an impression of the natural diversity of phytases, the enzymatic properties of six fungal phytases (phytases from Aspergillus niger, two strains of Aspergillus terreus, Aspergillus fumigatus, Emericella nidulans, and Myceliophthora thermophila) and of Escherichia coli phytase were characterized in more detail by addressing the following questions. (i) What are the specific activities and pH optima of wild-type phytases? (ii) What are the kinetics of phytic acid degradation, and what are the end products? (iii) Does the substrate specificity profile correlate with the results of in vitro experiments performed to determine phosphate liberation from feed samples? And (iv) what is the potential influence of modulators of enzymatic activity?
472 citations
429 citations
TL;DR: It is concluded that Y. lipolytica is a “safe-to-use” organism that causes rare opportunistic infections in severely immunocompromised or otherwise seriously ill people with other underlying diseases or conditions.
Abstract: Yarrowia lipolytica has been developed as a production host for a large variety of biotechnological applications. Efficacy and safety studies have demonstrated the safe use of Yarrowia-derived products containing significant proportions of Yarrowia biomass (as for DuPont's eicosapentaenoic acid-rich oil) or with the yeast itself as the final product (as for British Petroleum's single-cell protein product). The natural occurrence of the species in food, particularly cheese, other dairy products and meat, is a further argument supporting its safety. The species causes rare opportunistic infections in severely immunocompromised or otherwise seriously ill people with other underlying diseases or conditions. The infections can be treated effectively by the use of regular antifungal drugs, and in some cases even disappeared spontaneously. Based on our assessment, we conclude that Y. lipolytica is a "safe-to-use" organism.
363 citations
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TL;DR: A major unifying thread of the review is a consideration of how the changes occurring during and after ischemia conspire to produce damaging levels of free radicals and peroxynitrite to activate calpain and other Ca(2+)-driven processes that are damaging, and to initiate the apoptotic process.
Abstract: This review is directed at understanding how neuronal death occurs in two distinct insults, global ischemia and focal ischemia. These are the two principal rodent models for human disease. Cell dea...
2,960 citations
TL;DR: A comprehensive survey of the many intriguing facets of creatine (Cr) and creatinine metabolism is presented, encompassing the pathways and regulation of Cr biosynthesis and degradation, species and tissue distribution of the enzymes and metabolites involved, and of the inherent implications for physiology and human pathology.
Abstract: The goal of this review is to present a comprehensive survey of the many intriguing facets of creatine (Cr) and creatinine metabolism, encompassing the pathways and regulation of Cr biosynthesis an...
2,332 citations
TL;DR: Most of the mechanistic studies of fatigue are on isolated animal tissues, and another major challenge is to use the knowledge generated in these studies to identify the mechanisms of fatigue in intact animals and particularly in human diseases.
Abstract: Repeated, intense use of muscles leads to a decline in performance known as muscle fatigue. Many muscle properties change during fatigue including the action potential, extracellular and intracellular ions, and many intracellular metabolites. A range of mechanisms have been identified that contribute to the decline of performance. The traditional explanation, accumulation of intracellular lactate and hydrogen ions causing impaired function of the contractile proteins, is probably of limited importance in mammals. Alternative explanations that will be considered are the effects of ionic changes on the action potential, failure of SR Ca2+ release by various mechanisms, and the effects of reactive oxygen species. Many different activities lead to fatigue, and an important challenge is to identify the various mechanisms that contribute under different circumstances. Most of the mechanistic studies of fatigue are on isolated animal tissues, and another major challenge is to use the knowledge generated in these studies to identify the mechanisms of fatigue in intact animals and particularly in human diseases.
2,054 citations
TL;DR: This review describes cardiac energy metabolism, appraises the methods used for its assessment, evaluates the role of impaired energy metabolism in heart failure, and gives options for metabolic therapy.
Abstract: and it can severely reduce a patient’s quality of life. It consumes approximately 2% of the National Health Service budget in the United Kingdom, and in the United States, the total annual cost of treatment for heart failure is approximately $28 billion. Moreover, the financial burden of heart failure will increase in coming decades because of the aging population and the improved treatments of its causes. Over the past 20 years, there has been considerable progress in the treatment of chronic heart failure with angiotensin-converting–enzyme (ACE) inhibitors, 4,5 aldosterone antagonists, 6 beta-receptor blockers, 7,8 and resynchronization therapy. 9,10 Even with the very best of modern therapy, however, heart failure is still associated with an annual mortality rate of 10%. 10 The search for better treatments is one of the major challenges in cardiology. Chronic heart failure is multifactorial. There are many reasons why a human heart can fail, 11 but the available evidence suggests that the failing heart is an engine out of fuel — that is, altered energetics play an important role in the mechanisms of heart failure. For this reason, the modulation of cardiac metabolism has promise as a new approach to the treatment of heart failure. This review describes cardiac energy metabolism, appraises the methods used for its assessment, evaluates the role of impaired energy metabolism in heart failure, and gives options for metabolic therapy.
1,968 citations
TL;DR: The development of enzymes with improved properties for established technical applications and in the production of new enzymes tailor-made for entirely new areas of application where enzymes have not previously been used are studied.
Abstract: The effective catalytic properties of enzymes have already promoted their introduction into several industrial products and processes Recent developments in biotechnology, particularly in areas such as protein engineering and directed evolution, have provided important tools for the efficient development of new enzymes This has resulted in the development of enzymes with improved properties for established technical applications and in the production of new enzymes tailor-made for entirely new areas of application where enzymes have not previously been used
1,319 citations