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91.
Shuhei Yanase Ryosuke Yamada Shohei Kaneko Hideo Noda Tomohisa Hasunuma Tsutomu Tanaka Chiaki Ogino Hideki Fukuda Akihiko Kondo Professor 《Biotechnology journal》2010,5(5):449-455
We demonstrate direct ethanol fermentation from amorphous cellulose using cellulase-co-expressing yeast. Endoglucanases (EG) and cellobiohydrolases (CBH) from Trichoderma reesei, and β-glucosidases (BGL) from Aspergillus aculeatus were integrated into genomes of the yeast strain Saccharomyces cerevisiae MT8-1. BGL was displayed on the yeast cell surface and both EG and CBH were secreted or displayed on the cell surface. All enzymes were successfully expressed on the cell surface or in culture supernatants in their active forms, and cellulose degradation was increased 3- to 5-fold by co-expressing EG and CBH. Direct ethanol fermentation from 10 g/L phosphoric acid swollen cellulose (PASC) was also carried out using EG-, CBH-, and BGL-co-expressing yeast. The ethanol yield was 2.1 g/L for EG-, CBH-, and BGL-displaying yeast, which was higher than that of EG- and CBH-secreting yeast (1.6 g/L ethanol). Our results show that cell surface display is more suitable for direct ethanol fermentation from cellulose. 相似文献
92.
Akira Takeda Hirofumi Tsukada Yuichi Takaku Shun’ichi Hisamatsu 《Plant and Soil》2010,330(1-2):383-392
Time-dependent changes of phytoavailability of Sr after adding it to the soil were studied for better prediction of radioactive Sr behavior in soil–plant systems. Strontium-86 enriched stable isotope was added to a soil sample collected from a field of humus-rich Andosol. Plant uptake and extractability of Sr in the soil were assessed at given times after the addition during a 12-month period including repeated drying-rewetting. Proportion of the added Sr extracted by 1 M ammonium acetate solution from the soil was 45–58% throughout the period, which corresponded to that of long-time aged 90Sr in the soil. Pot cultivations of orchardgrass (Dactylis glomerata) and red clover (Trifolium pratense) were carried out starting with uncropped soil for four weeks five times during the experiment. Clear time-dependent changes were not observed in uptake of the added Sr by the plants. Aging is unlikely to decrease Sr availability over time. The labile form of Sr determined with the isotopic dilution method was approximately 15% of total soil Sr, and more than the percentage of the extractable Sr in the soil. The results suggest that a part of the non-extractable forms of Sr in the soil would be available to the plant. 相似文献
93.
Identification of the FANCI protein, a monoubiquitinated FANCD2 paralog required for DNA repair 总被引:10,自引:0,他引:10
Smogorzewska A Matsuoka S Vinciguerra P McDonald ER Hurov KE Luo J Ballif BA Gygi SP Hofmann K D'Andrea AD Elledge SJ 《Cell》2007,129(2):289-301
Fanconi anemia (FA) is a developmental and cancer-predisposition syndrome caused by mutations in genes controlling DNA interstrand crosslink repair. Several FA proteins form a ubiquitin ligase that controls monoubiquitination of the FANCD2 protein in an ATR-dependent manner. Here we describe the FA protein FANCI, identified as an ATM/ATR kinase substrate required for resistance to mitomycin C. FANCI shares sequence similarity with FANCD2, likely evolving from a common ancestral gene. The FANCI protein associates with FANCD2 and, together, as the FANCI-FANCD2 (ID) complex, localize to chromatin in response to DNA damage. Like FANCD2, FANCI is monoubiquitinated and unexpectedly, ubiquitination of each protein is important for the maintenance of ubiquitin on the other, indicating the existence of a dual ubiquitin-locking mechanism required for ID complex function. Mutation in FANCI is responsible for loss of a functional FA pathway in a patient with Fanconi anemia complementation group I. 相似文献
94.
Kawamoto Y Shotake T Nozawa K Kawamoto S Tomari K Kawai S Shirai K Morimitsu Y Takagi N Akaza H Fujii H Hagihara K Aizawa K Akachi S Oi T Hayaishi S 《Primates; journal of primatology》2007,48(1):27-40
We investigated the diversity and phylogeography of mitochondrial DNA (mtDNA) in Japanese macaques (Macaca fuscata), an endemic species in Japan that has the northernmost distribution of any non-human primate species. DNA samples from 135
localities representing the entire range of this species were compared. A total of 53 unique haplotypes were observed for
the 412-bp partial mtDNA control region sequence, with length variation distinguishing the two subspecies. Clustering analyses
suggested two putative major haplogroups, of which one was geographically distributed in eastern Japan and the other in western
Japan. The populations in the east showed lower mtDNA diversity than those in the west. Phylogeographical relationships of
haplotypes depicted with minimum spanning network suggested differences in population structure. Population expansion was
significant for the eastern but not the western population, suggesting establishment of the ancestral population was relatively
long ago in the west and recent in the east. Based on fossil evidence and past climate and vegetation changes, we inferred
that the postulated population expansion may have taken place after the last glacial period (after 15,000 years ago). Mitochondrial
DNA showed contrasting results in both variability and phylogenetic status of local populations to those of previous studies
using protein variations, particularly for populations in the periphery of the range, with special inference on habitat change
during the glacial period in response to cold adaptation.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
95.
Hossain MT Soga K Wakabayashi K Kamisaka S Fujii S Yamamoto R Hoson T 《Journal of plant physiology》2007,164(4):385-393
Effects of silicon on the mechanical and chemical properties of cell walls in the second leaf of oat (Avena sativa L.) seedlings were investigated. The cell wall extensibility in the basal region of the second leaf was considerably higher than that in the middle and subapical regions. Externally applied silicon increased the cell wall extensibility in the basal region, but it did not affect the extensibility in the middle and subapical regions. The amounts of cell wall polysaccharides and phenolic compounds, such as diferulic acid (DFA) and ferulic acid (FA), per unit length were lower in the basal region than in the middle and subapical regions of the leaf, and silicon altered these amounts in the basal region. In this region, silicon decreased the amounts of matrix polymers and cellulose per unit length and of DFA and FA, both per unit length and unit matrix polymer content. Silicon treatment also lowered the activity of phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) in the basal region. In contrast, the amount of silicon in cell walls increased in response to silicon treatment in three regions. These results suggest that in the basal region, silicon reduces the net wall mass and the formation of phenolic acid-mediated cross-linkages between wall polysaccharides. Such modifications of wall architecture may be responsible for the silicon-induced increase in the cell wall extensibility in oat leaves. 相似文献
96.
Fongmoon D Shetty AK Basappa Yamada S Sugiura M Kongtawelert P Sugahara K 《The Journal of biological chemistry》2007,282(51):36895-36904
Chondroitin sulfate K (CS-K) from king crab cartilage rich in rare 3-O-sulfated glucuronic acid (GlcUA(3S)) displayed neuritogenic activity and affinity toward various growth factors like CS-E from squid cartilage. CS-K-mediated neuritogenesis of mouse hippocampal neurons in culture was abolished by digestion with chondroitinase (CSase) ABC, indicating the possible involvement of GlcUA(3S). However, identification of GlcUA(3S) in CS chains by conventional high performance liquid chromatography has been hampered by its CSase ABC-mediated degradation. To investigate the degradation process, an authentic CS-E tetrasaccharide, Delta4,5HexUA-GalNAc(4S)-GlcUA(3S)-GalNAc(4S), was digested with CSase ABC, and the end product was identified as GalNAc(4S) by electrospray ionization mass spectrometry (ESI-MS). Putative GalNAc(6S) and GalNAc(4S,6S), derived presumably from GlcUA(3S)-GalNAc(6S) and GlcUA(3S)-GalNAc(4S,6S), respectively, were also detected by ESI-MS in the CSase ABC digest of a CS-E oligosaccharide fraction resistant to CSases AC-I and AC-II. Intermediates during the CSase ABC-mediated degradation of Delta4,5HexUA(3S)-GalNAc(4S) to GalNAc(4S) were identified through ESI-MS of a partial CSase ABC digest of a CS-K tetrasaccharide, GlcUA(3S)-GalNAc(4S)-GlcUA(3S)-GalNAc(4S), and the conceivable mechanism behind the degradation of the GlcUA(3S) moiety was elucidated. Although a fucose branch was also identified in CS-K, defucosylated CS-K exhibited greater neuritogenic activity than the native CS-K, excluding the possibility of the involvement of fucose in the activity. Rather, (3S)-containing disaccharides are likely involved. These findings will enable us to detect GlcUA(3S)-containing disaccharides in CS chains to better understand CS-mediated biological processes. 相似文献
97.
Tsujimoto H Hara K Tsukada Y Huang CC Kawashima Y Arakaki M Okayasu H Mimura H Miwa N 《Bioorganic & medicinal chemistry letters》2007,17(17):4771-4777
This paper describes the process of encapsulating hair growing ingredients in the PLGA nanospheres by emulsion solvent diffusion method and investigates the feasibility of using the PLGA nanospheres as the DDS (Drug delivery System) carriers for delivering various hair growing ingredients to hair follicles. In-vitro and in-vivo tests were conducted to verify the performances of encapsulated PLGA nanospheres with three different hair growing ingredients. In the in-vitro tests, the scalp-pore permeability of hair growing ingredient encapsulated PLGA nanospheres (dispersed in the PBS solution) was examined using human scalp biopsies in a modified Bronaugh diffusion chamber in comparison to that of the control samples containing the hair growing ingredient in the PBS solution. Furthermore, the hair growing effect of the encapsulated PLGA nanospheres was evaluated with the C3H mice in the in-vivo tests. By observing the fluorescence intensity of the ingredients, as shown in the cross-section photographs of the human scalp biopsies, it was found that the dispersion liquids containing hair growing ingredient encapsulated PLGA nanospheres exerted a scalp-pore permeability 2.0- to 2.5-fold more marked than that of the control samples. Also, the hair growing activities were enhanced by using the encapsulated PLGA nanospheres, which transformed the hair growth cycle from the resting phase to the growing phase. As a result, the degree of hair growth was improved significantly. These results suggested that the PLGA nanosphere can be a new DDS carrier for delivering hair growing ingredients and drugs to the hair follicles. 相似文献
98.
Shi J Yamashita T Todo A Nitoda T Izumi M Baba N Nakajima S 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(11-12):821-825
By using a new bioassay-guided method, 2-hydroxy-4-methoxybenzaldehyde isolated from the root bark of Periploca sepium, a traditional Chinese medicine, showed repellent activity against the olive weevil (Dyscerus perforatus) at 62.5, 125, 250 and 500 microg/disc, respectively. In addition, it also exhibited antinematodal activity against Bursaphelenchus xylophilus at a minimum effective dose of 200 microg/ball. The three related compounds obtained were also evaluated for the above-mentioned bioactivities. 相似文献
99.
100.