Cyanate from alkaline hydrolysis of cyanogen bromide-activated polysaccharides

Alkaline treatment (pH 12) of cyanogen bromide-activated Sepharose and Sephadex, both with or without coupled protein, released a thiol protease inactivator. It was successfully isolated by the combination of Sephadex G-10 gel filtration and Dowex 1-X2 ion-exchange chromatography. Infrared and chemical analysis show it to be the cyanate ion. Barbituric-pyridine colorimetric analysis, capacity test, and other evidence suggest that the carbamate group in the activated polysaccharides is the most likely precursor of the cyanate.     

Novel azulene-based derivatives as potent multi-receptor tyrosine kinase inhibitors

A series of azulene-based derivatives were synthesized as potent inhibitors for receptor tyrosine kinases such as FMS-like tyrosine kinase 3 (FLT-3). Systematic side chain modification of prototype 1a was carried out through SAR studies. Analogue 22 was identified from this series and found to be one of the most potent FLT-3 inhibitors, with good pharmaceutical properties, superior efficacy, and tolerability in a tumor xenograft model.     

Genetic relatedness of Trichoderma sect. Pachybasium species based on molecular approaches

Molecular approaches including internal transcribed spacer (ITS) sequences of ribosomal DNA, universal primer polymerase chain reaction (UP-PCR) fingerprinting, and DNA-DNA hybridization were used to study the genetic relatedness of species within Trichoderma sect. Pachybasium. In the analysis of ITS and 5.8S sequences of ribosomal DNA, parsimony analysis demonstrated that forty-one strains were distributed into five main groups supported by high bootstrap values. The species of Trichoderma sect. Pachybasium were clustered into groups I, II, and IV, with the strains of Trichoderma fasculatum and Trichoderma strictipile forming a separate branch, an independent group V. Some species within each group showed nearly identical sequence differences (fewer than 1-3 bp). UP-PCR and DNA-DNA hybridization were further used to clarify the genetic relatedness of these species with highly similar ITS sequences. Highly similar or identical UP-PCR profiles and high values of DNA complementarity (>70%) were observed among some species, Trichoderma hamatum and Trichoderma pubescens; Trichoderma croceum, Trichoderma polysporum and Trichoderma album, Trichoderma crassum and Trichoderma flavofuscum; and Trichoderma strictipile and Trichoderma fasciculatum. Although every species can be differentiated morphologically, the species showed highly similar molecular characteristics in the above cases, indicating that they could be conspecific. However, in some cases (Trithoderma longipile, T. crassum and T. flavofuscum; Trichoderma fertile and Trichoderma minutisporum; Trichoderma tomentosum, Trichoderma inhamatum and Trichoderma harzianum) there were discriminative patterns of UP-PCR and (or) low levels (<50%) of DNA-DNA hybridization; even their ITS sequences were similar, suggesting a closely phylogenetic relationship.     

Cell growth restoration and high level protein expression by the promoter of hexose transporter, HXT7, from Saccharomyces cerevisiae

The promoters of high-affinity hexose transporter, HXT6 and HXT7, are sufficient for complementary expression of invertase to restore the growth of Saccharomyces cerevisiae in raffinose medium. The HXT7 promoter produced higher invertase activity at 139- and 30-fold of the basal activity in strains GN 3C.2 and W303-1, respectively. In addition, the HXT7 promoter expressed 3- to 9-fold more of enhanced green fluorescent protein than that of the constitutive ADH1 in three different S. cerevisiae strains, even during short-term incubation in glucose medium. Therefore, HXT7 promoter could be used for heterologous protein expression in S. cerevisiae.     

Synthesis and structure–activity relationship of 6-arylureido-3-pyrrol-2-ylmethylideneindolin-2-one derivatives as potent receptor tyrosine kinase inhibitors

A series of new ureidoindolin-2-one derivatives were synthesized and evaluated as inhibitors of receptor tyrosine kinases. Investigation of structure–activity relationships at positions 5, 6, and 7 of the oxindole skeleton led to the identification of 6-ureido-substituted 3-pyrrolemethylidene-2-oxindole derivatives that potently inhibited both the vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) families of receptor tyrosine kinases. Several derivatives showed potency against the PDGFR inhibiting both its enzymatic and cellular functions in the single-digit nanomolar range. Among them, compound 35 was a potent inhibitor against tyrosine kinases, including VEGFR and PDGFR families, as well as Aurora kinases. Inhibitor 36 (non-substituted on the pyrrole or phenyl ring) had a moderate pharmacokinetic profile and completely inhibited tumor growth initiated with the myeloid leukemia cell line, MV4-11, in a subcutaneous xenograft model in BALB/c nude mice.     

Reidentification of cellulolytic enzyme-producing Trichoderma strains W-10 and G-39

Strain W-10, originally identified as Trichoderma koningii, and its supposed mutant G-39, published for production and gene expression of cellulase and xylanase, demonstrated morphological characteristics distinct from those of T. koningii, respectively. To clarify the identification derived from morphological characteristics, several methods were used, including electrophoretic karyotyping, internal transcribed spacer (ITS) analysis of rDNA, and polymerase chain reaction (PCR) fingerprinting using the universal primer L45. All the molecular characteristics showed that strains G-39 and W-10 were identical to T. reesei and T. longibrachiatum, respectively. The results strongly supported that T. koningii G-39 and W-10 should be reassigned as T. reesei and T. longibrachiatum, respectively. Strain G-39 should be considered a mutant from T. reesei QM9414 whose spores were contaminated with those of strain W-10 during a laboratory operation. According to this, we declare that T. koningii G-39 and W-10 must be renamed as T. reesei and T. longibrachiatum, respectively.