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991.
A novel Gram stain-negative, catalase- and oxidase-positive, strictly aerobic bacterium, designated strain H50T, was isolated from an amphioxus breeding zone in the coastal region of the Yellow Sea, China. Cells were observed to be ovoid or short rods, lacked flagella and were found to contain bacteriochlorophyll a. Poly-beta-hydroxybutyrate was found to be accumulated. The temperature range for growth was determined to be 0–37 °C (optimum 28–37 °C). The halotolerance range for growth is 1–15 % NaCl (optimum 2–7 %). The pH range for growth is 6.0–8.0 (optimum 7.0). The major fatty acids were identified as C18:1ω7c and C16:0. The following polar lipids were found to be present: diphosphatidylglycerol, phosphatidylglycerol and a lipid. The predominant respiratory quinone was determined to be Q-10. DNA G+C content was determined to be 57.7 mol%. Strain H50T exhibited the highest 16S rRNA gene sequence similarity to Pelagicola litoralis DSM 18290T (96.1 %), Roseovarius mucosus DSM 17069T (95.8 %) and Roseovarius tolerans DSM 11457T (95.7 %). In the phylogenetic trees, strain H50T was clustered with the genus Roseovarius but not Pelagicola. On the basis of phenotypic, chemotaxonomic and genotypic data, strain H50T is considered to represent a novel species in the genus Roseovarius, for which the name Roseovarius marisflavi sp. nov. is proposed. The type strain is H50T (=CGMCC 1.10799T=JCM 17553T). 相似文献
992.
Antimicrobial peptides (AMPs) are recognized as the potential substitutions for common antibiotics. Flexibility has been demonstrated to be a dominant on antimicrobial activity of an AMP, similar to the structural parameters such as hydrophobicity and hydrophobic moment as well as positive charge. To better understand the effect of flexibility on antimicrobial activity, we herein examined seventy-eight peptides derived from nine different species. Defined as a weighted average of amino acid flexibility indices over whole residue chain of AMP, flexibility index was used to scale the peptide flexibility and indicated to be a reflection of mechanical properties such as tensile and flexural rigidities. The results demonstrated that flexibility index is relevant to but different from other structural properties, may enhance activity against Escherichia coli for stiff clustered peptides or reduce activity against E. coli for flexible clustered peptides, and its optimum occurs at about − 0.5. This effect of flexibility on antimicrobial activity may be involved to the antimicrobial actions, such as stable peptide-bound leaflet formation and sequent stress concentration in target cell membrane, mechanically. The present results provide a new insight in understanding antimicrobial actions and may be useful in seeking for a new structure–activity relationship for cationic and amphipathic α-helical peptides. 相似文献
993.
The amino acid composition of Nephila clavipes dragline silk fiber was determined by conducting 1H nuclear magnetic resonance (NMR) spectroscopy experiments on acid-hydrolyzed material. N. clavipes dragline silk was found to consist of 43.0 ± 0.6% Gly, 29.3 ± 0.2% Ala, 9.1 ± 0.1% Glx, 4.0 ± 0.1% Leu, 3.3 ± 0.1% Tyr, 3.4 ± 0.2% Ser, 2.7 ± 0.1% Pro, 2.1 ± 0.1% Arg, 1.07 ± 0.05% Asx, 0.96 ± 0.05% Val, 0.48 ± 0.03% Thr, 0.35 ± 0.03% Phe, and 0.28 ± 0.03% Ile. Compared with standard chromatography-based amino acid analysis (AAA), the chemical resolution of NMR allows for an amino acid solution to be characterized without separation and is shown to provide considerably higher precision. This allows for more accurate statistics on the variability of amino acids in spider dragline silk. In general, this 1H NMR AAA technique is applicable to a large range of proteins and peptides for precise composition characterization, especially when the precise content of a minor component is critical and relatively large amounts of sample are available (microgram to milligram quantities). 相似文献
994.
Yan hong Gao Ying YuXiao gang Hu Yu juan CaoJian zhong Wu 《Analytical biochemistry》2013,440(2):205-211
Hormones regulate the mechanism of plant growth and development, senescence, and plants’ adaptation to the environment; studies of the molecular mechanisms of plant hormone action are necessary for the understanding of these complex phenomena. However, there is no measurable signal for the hormone signal transduction process. We synthesized and applied a quantum dot-based fluorescent probe for the labeling of jasmonic acid (JA) binding sites in plants. This labeling probe was obtained by coupling mercaptoethylamine-modified CdTe quantum dots with JA using N-hydroxysuccinimide (NHS) as a coupling agent. The probe, CdTe–JA, was characterized by transmission electron microscopy, dynamic light scattering, and fluorescent spectrum and applied in labeling JA binding sites in tissue sections of mung bean seedlings and Arabidopsis thaliana root tips. Laser scanning confocal microscopy (LSCM) revealed that the probe selectively labeled JA receptor. The competition assays demonstrated that the CdTe–JA probe retained the original bioactivity of JA. An LSCM three-dimensional reconstruction experiment demonstrated excellent photostability of the probe. 相似文献
995.
Adel Shalata Maria C. Ramirez Robert J. Desnick Nolan Priedigkeit Christoph Buettner Claudia Lindtner Mohammed Mahroum Muhammad Abdul-Ghani Feng Dong Nazik Arar Olga Camacho-Vanegas Rui Zhang Sandra C. Camacho Ying Chen Mwafaq Ibdah Ralph DeFronzo Virginia Gillespie Kevin Kelley Brian D. Dynlacht Sehyun Kim Marc J. Glucksman Zvi U. Borochowitz John A. Martignetti 《American journal of human genetics》2013
996.
997.
Guoguo Zhu Yingcheng Zheng Lianglu Zhang Yingying Shi Wenhua Li Zhongchun Liu Biwen Peng Jun Yin Wanhong Liu Xiaohua He 《Biochemical and biophysical research communications》2013
Coxsackievirus A16 (CA16) infection, which is responsible for hand, foot and mouth disease (HFMD), has become a common health problem in Asia due to the prevalence of the virus. Thus, it is important to understand the pathogenesis of CA16 infection. Viruses that induce endoplasmic reticulum (ER) stress are confronted with the unfolded protein response (UPR), which may lead to apoptotic cell death and influence viral replication. In this study, we found that CA16 infection could induce apoptosis and ER stress in RD cells. Interestingly, apoptosis via the activation of caspase-3, -8 and -9 in the extrinsic or intrinsic apoptotic pathways in RD cells was inhibited by 4-phenyl butyric acid (4PBA), a chemical chaperone that reduces ER stress. These results suggest that CA16 infection leads to ER stress, which in turn results in prolonged ER stress-induced apoptosis. This study provides a new basis for understanding CA16 infection and host responses. 相似文献
998.
999.
Yuxiang Zeng Liangyong Ma Zhijuan Ji Zhihua Wen Ximing Li Chunhai Shi Changdeng Yang 《Biologia》2013,68(1):82-90
A rice lesion mimic mutant, lm3, was obtained by the mutagenesis of an indica cultivar, 93-11, using γ-ray radiation. Brownish lesions appeared on the leaves of lm3 at the young seedling stage and persisted until the ripening stage. The lm3 mutant was characterised by a shorter plant height and delayed heading compared with the wild-type 93-11. A genetic analysis indicated that the lesion mimic phenotype was controlled by a single recessive gene. Using simple sequence repeat (SSR) markers, the target gene LM3 was first located between marker RM5748 and RM14906 on chromosome 3. We then developed Insertion-Deletion (InDel) markers to fine-map LM3, and the locus was localised to a 29 kb region defined by two InDel markers, In12571 and In12600. Five ORFs were predicted in the candidate region, and DNA sequencing detected a single-nucleotide polymorphism (SNP) in the coding region of LOC Os03g21900. The SNP in the fourth exon (C in 93-11; T in lm3) of LOC_Os03g21900 results in the substitution of a proline (P) with a serine (S) at the 140th amino acid of the deduced uroporphyrinogen decarboxylase protein. We did not detect polymorphisms in the other predicted ORF regions between lm3 and 93-11. These results suggest that LOC_Os03g21900 is the most likely candidate gene for LM3. 相似文献
1000.
Shan Cheng Yang Li Ying Yang Duiping Feng Longyan Yang Qian Ma Shuai Zheng Ran Meng Shuhui Wang Songlin Wang Wen G. Jiang Junqi He 《FEBS letters》2013
Na+/H+ exchanger regulatory factor 1 (NHERF1) is a scaffold protein known to interact with a number of cancer-related proteins. nherf1 Mutations (K172N and D301V) were recently identified in breast cancer cells. To investigate the functional properties of NHERF1, wild-type and cancer-derived nherf1 mutations were stably expressed in SKMES-1 cells respectively. NHERF1-wt overexpression suppressed the cellular malignant phenotypes, including proliferation, migration, and invasion. nherf1 Mutations (K172N and D301V) caused complete or partial loss of NHERF1 functions by affecting the PTEN/NHERF1/PDGFRβ complex formation, inactivating NHERF1 inhibition of PDGF-induced AKT and ERK activation, and attenuating the tumor-suppressor effects of NHERF1-wt. These results further demonstrated the functional consequences of breast cancer-derived nherf1 mutations (K172N and D301V), and suggested the causal role of NHERF1 in tumor development and progression. 相似文献