The development of microbes for conducting bioprocessing synthetic biology involves design-build-test-learn (DBTL) cycles. To aid the designing step, we developed a computational technique that suggests next genetic modifications on the basis of relatedness to the user's design history of genetic modifications accumulated through former DBTL cycles conducted by the user. This technique, which comprehensively retrieves well-known designs related to the history, involves searching text for previous literature and then mining genes that frequently co-occur in the literature with those modified genes.
View Article and Find Full Text PDFLight-responsive regulation of ciliary motility is known to be conducted through modulation of dyneins, but the mechanism is not fully understood. Here, we report a novel subunit of the two-headed f/I1 inner arm dynein, named DYBLUP, in animal spermatozoa and a unicellular green alga. This subunit contains a BLUF (sensors of blue light using FAD) domain that appears to directly modulate dynein activity in response to light.
View Article and Find Full Text PDFBioinformatics
December 2020
Motivation: Exploring metabolic pathways is one of the key techniques for developing highly productive microbes for the bioproduction of chemical compounds. To explore feasible pathways, not only examining a combination of well-known enzymatic reactions but also finding potential enzymatic reactions that can catalyze the desired structural changes are necessary. To achieve this, most conventional techniques use manually predefined-reaction rules, however, they cannot sufficiently find potential reactions because the conventional rules cannot comprehensively express structural changes before and after enzymatic reactions.
View Article and Find Full Text PDFSea anemones belonging to the genera and have a remarkable symbiotic relationship with hermit crabs. These symbiotic sea anemones produce a shell-like structure, called a "carcinoecium," that covers and extends over the gastropod shell of the host hermit crab as hermit crabs grow. This structure has been described as "chitinous carcinoecium" or "chitinous coating.
View Article and Find Full Text PDFIn the ascidian Ciona robusta (formerly C. intestinalis type A), the mechanism underlying sperm penetration through the egg investment remains unknown. We previously reported that proteins containing both an astacin metalloprotease domain and thrombospondin type 1 repeats are abundant in the sperm surface protein-enriched fraction of C.
View Article and Find Full Text PDFPeanut agglutinin (PNA) is an established marker of the mammalian acrosome. However, we observed that PNA specifically binds to a unique intracellular structure alongside the nucleus in ascidian sperm. Here, we characterize the PNA-binding structure in sperm of marine invertebrates.
View Article and Find Full Text PDFSnake venom metalloproteases (SVMPs) are members of the a disintegrin and metalloprotease (ADAM) family of proteins, as they possess similar domains. SVMPs are known to elicit snake venom-induced haemorrhage; however, the target proteins and cleavage sites are not known. In this work, we identified a target protein of vascular apoptosis-inducing protein 1 (VAP1), an SVMP, relevant to its ability to induce haemorrhage.
View Article and Find Full Text PDFSperm proteins mediating sperm-egg interaction should be exhibited on the sperm surface, or exposed or released when sperm approach an egg. In ascidians (protochordates), sperm undergo a sperm reaction, characterized by enhanced sperm motility and mitochondrial swelling and shedding on contact with the vitelline coat (VC) or by treatment with Ca(2+) ionophore. Here, proteomic analysis was conducted on sperm exudates and sperm surface proteins using ionomycin-induced sperm reaction and cell-impermeable labeling in Ciona intestinalis type A (C.
View Article and Find Full Text PDFSilkworms serve as promising bioreactors for the production of recombinant proteins, including glycoproteins and membrane proteins, for structural and functional protein analyses. However, lack of methodology for stable isotope labeling has been a major deterrent to using this expression system for nuclear magnetic resonance (NMR) structural biology. Here we developed a metabolic isotope labeling technique using commercially available silkworm larvae.
View Article and Find Full Text PDFWe successfully developed a method for metabolic isotope labeling of recombinant proteins produced in transgenic tobacco. This enabled assessment of structural integrity of plant-derived therapeutic antibodies by NMR analysis. A variety of expression vehicles have been developed for the production of promising biologics, including plants, fungi, bacteria, insects, and mammals.
View Article and Find Full Text PDFThe recent patent expirations of erythropoietin (EPO) have promoted the development of biosimilars. Two and one biosimilar EPO products were approved in 2007 in Europe and in 2010 in Japan, respectively. Glycosylation heterogeneity of EPO is very complex, and its pattern has a large impact on its in vivo activity.
View Article and Find Full Text PDFHuman insulin and insulin lispro (lispro), a rapid-acting insulin analog, have identical primary structures, except for the transposition of a pair of amino acids. This mutation results in alterations in their higher order structures, with lispro dissociating more easily than human insulin. In our previous study performed using hydrogen/deuterium exchange mass spectrometry (HDX/MS), differences were observed in the rates and levels of deuteration among insulin analog products, which were found to be related to their self-association stability.
View Article and Find Full Text PDFGlycosylation of cells is known to alter with several biological events such as cell differentiations and proliferations as well as some diseases. "Glycomic approaches", comprehensive qualitative and quantitative glycan analyses of the cells, have become increasingly important as a means of discovering biomarkers that have the potential of being used as disease diagnostic markers and molecular markers for cell characterizations. In this paper, we introduce a method of quantitative glycan profiling by liquid chromatography/mass spectrometry with a combination of an isotope tagging method.
View Article and Find Full Text PDFInsulin analog products for subcutaneous injection are prepared as solutions in which insulin analog molecules exist in several oligomeric states. Oligomeric stability can affect their onset and duration of action and has been exploited in designing them. To investigate the oligomeric stability of insulin analog products having different pharmacokinetics, we performed hydrogen/deuterium exchange mass spectrometry (HDX/MS), which is a rapid method to analyze dynamic aspects of protein structures.
View Article and Find Full Text PDFThe sorting nexin (SNX) family proteins, which contain a Phox homology (PX) domain, play crucial roles in regulating the intracellular membrane trafficking of the endocytic pathway. The proper coordination of this pathway is important for axonal elongation; however, little is known about the expression and intracellular dynamics of the SNX members during the formation of the nervous system. Here the authors found that SNX18, which belongs to the Src-homology-3-PX-Bin/Amphiphysin/Rvs domain-containing SNX subfamily, was specifically expressed in differentiating motor neurons in the chick and mouse embryonic spinal cord.
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