Atsushi Koide

Learn More
Sporulation in Bacillus subtilis depends on an intact oligopeptide transport system, the Opp system. Mutants in opp sporulate poorly but second-site revertants can be found that restore sporulation and peptide transport. These second-site mutations were found in a second oligopeptide transport system, app, in which the peptide-binding protein, AppA, is(More)
An isopullulanase (IPU) from Aspergillus niger ATCC9642 hydrolyzes alpha-1,4-glucosidic linkages of pullulan to produce isopanose. Although IPU does not hydrolyze dextran, it is classified into glycoside hydrolase family 49 (GH49), major members of which are dextran-hydrolyzing enzymes. IPU is highly glycosylated, making it difficult to obtain its crystal.(More)
Oligopeptides are transported into Bacillus subtilis by two ABC transport systems, App and Opp. Transcription of the operon encoding the Opp system was found to occur during exponential growth, whereas the app operon was induced at the onset of stationary phase. Transcription of both operons was completely curtailed by overproduction of the ScoC regulator(More)
Alkaline phosphatase (APase) is induced as a culture enters stationary phase because of limiting phosphate. The results presented here show that expression of APase is regulated both negatively and positively. PhoP, a homolog of a family of bacterial transcription factors, and PhoR, a homolog of bacterial histidine protein kinases, are required for(More)
Eight new phenolic glycosides, cucurbitosides F-M (1-8), were isolated from the seeds of Cucurbita pepo. Their structures were elucidated as 4-(2-hydroxyethyl)phenyl 5-O-(2-S-2-methylbutyryl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (1), 4-(2-hydroxyethyl)phenyl 5-O-(3-methylbutyryl)-beta-d-apiofuranosyl(l-->2)-beta-d-glucopyranoside (2),(More)
Undeniable signature is a kind of signatures that the validity or invalidity of a signature can only be verified with the help of the signer. On the other hand, the concept of blind signature is to enable a user to obtain a signature on a message which is unknown to the signer. Following these pioneer works, extended version of these schemes such as(More)
A restricted universal designated verifier signature scheme proposed by Huang et al., which is a variant of digital signatures, allows a signature holder to convince at most t designated verifiers.The signature will become publicly verifiable when the signature holder uses the signature for t+1 times.The applications of this type of signatures are expected(More)
A sanitizing signature scheme, which is a variant of digital signatures, enables a trusted party named sanitizer to modify parts of signed documents without corresponding to the signer. A lot of sanitizing signature schemes have been proposed since 2001. However these schemes are suitable for table-style documents, but none of them are considered for(More)
Introduction Enzymes hydrolyze pullulan are useful in the production of various oligosaccharides. Isopullulanase (IPU) from Aspergillus niger ATCC9642 was originally reported to be an enzyme which hydrolyzes specific sites of pullulan to produce isopanose (Glc-α-(1→4)-Glc-α(1→6)-Glc). Although IPU does not hydrolyze starch, the enzyme hydrolyzes substrates(More)
  • 1