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Glycated proteins, particularly glycated hemoglobin A1c, are important markers for assessing the effectiveness of diabetes treatment. Convenient and reproducible assay systems based on the enzyme fructosyl amino acid oxidase (FAOD) have become attractive alternatives to conventional detection methods. We review the available FAOD-based assays for measurement of glycated proteins as well as the recent advances and future direction of FAOD research. Future research is expected to lead to the next generation of convenient, simple, and economical sensors for glycated protein, ideally suited for point-of-care treatment and self-monitoring applications.

a b s t r a c tThis paper develops a model-free method to estimate the dynamics of free-flying objects. We take a realistic perspective to the problem and investigate tracking accurately and very rapidly the trajectory and orientation of an object so as to catch it in flight. We consider the dynamics of complex objects where the grasping point is not located at the center of mass.To achieve this, a density estimate of the translational and rotational velocity is built based on the trajectories of various examples. We contrast the performance of six non-linear regression methods (Support Vector Regression (SVR) with Radial Basis Function (RBF) kernel, SVR with polynomial kernel, Gaussian Mixture Regression (GMR), Echo State Network (ESN), Genetic Programming (GP) and Locally Weighted Projection Regression (LWPR)) in terms of precision of recall, computational cost and sensitivity to choice of hyper-parameters. We validate the approach for real-time motion tracking of 5 daily life objects with complex dynamics (a ball, a fully-filled bottle, a half-filled bottle, a hammer and a pingpong racket). To enable real-time tracking, the estimated model of the object's dynamics is coupled with an Extended Kalman Filter for robustness against noisy sensing.

A three-dimensional structural model of fructosyl amine oxidase from the marine yeast Pichia N1-1 was generated using the crystal structure of monomeric sarcosine oxidase from Bacillus sp. B-0618 as template. The putative active site region was investigated by site-directed mutagenesis, identifying several amino acid residues likely playing important roles in the enzyme reaction. Asn354 was identified as a residue that plays an important role in substrate recognition and that can be substituted in order to change substrate specificity while maintaining high catalytic activity. While the Asn354Ala substitution had no effect on the V max K m -1 value for fructosyl valine, the V max K m -1 value for fructosyl-e N-lysine was decreased 3-fold, thus resulting in a 3-fold improvement in specificity for fructosyl valine over fructosyl-e N-lysine.

Current enzymatic methods for the analysis of glycated proteins use flavoenzymes that catalyze the oxidative deglycation of fructosyl peptides, designated as fructosyl peptidyl oxidases (FPOXs). However, as FPOXs are oxidases, the signals derived from electron mediator-type electrochemical monitoring based on them are affected by dissolved O(2). Improvement of dye-mediated dehydrogenase activity of FPOXs and its application to enzyme electrode construction were therefore undertaken. Saturation mutagenesis study on Asn56 of FPOX from Phaeosphaeria nodorum, produced mutants with marked decreases in the catalytic ability to employ O(2) as the electron acceptor, while showing higher dye-mediated dehydrogenase activity employing artificial electron acceptors than the parental enzyme. Thus constructed virtually fructosyl peptide dehydrogenase, Asn56Ala, was then applied to produce an enzyme electrode for the measurement of fructosyl-(α) N-valyl-histidine (f-(α)Val-His), the protease-digested product of HbA1c. The enzyme electrode could measure f-(α)Val-His in the physiological target range in air.

Docking models of fructosyl amine oxidase (FAOD) from the marine yeast Pichia N1-1 (N1-1 FAOD) with the substrates fructosyl valine (f-Val) and fructosyl-(epsilon)N-lysine (f-(epsilon)Lys) were produced using three-dimensional protein model as reported previously (Miura et al., 2006, Biotechnol. Lett., 28, 1895-1900). The residues involved in recognition of substrates were proposed, particularly Asn354, which interacts closely with f-(epsilon)Lys, but not with f-Val. Substitution of Asn354 to histidine and lysine simultaneously resulted in an increase in activity of f-val and a decrease in activity of f-(epsilon)Lys and thus, increasing the specificity for f-Val from 13- to 19-fold. In addition to creating two mutant FAODs with great potential for the measurement of glycated hemoglobin, we have provided the first structural model of substrate binding with eukaryotic FAOD, which is expected to contribute to further investigation of FAOD.

Abstract-In this paper, we consider a novel approach to control the timing of motions when these are encoded with autonomous dynamical systems(DS). Accurate timing of motion is crucial if a robot must synchronize its movement with that of a fast moving object. In previous work of ours [1], we developed an approach to encode robot motion into DS. Such a timeindependent encoding is advantageous in that it offers robustness against violent perturbation by adapting on the fly the trajectory while ensuring high accuracy at the target. We propose here an extension of the system that allows to control the timing of the motion while still benefitting from all the robustness properties deriving from the time-independent encoding of the DS. We validate the approach in experiments where the iCub robot learns from human demonstrations to catch a ball on the fly.