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981.
982.
Fernanda Gorga Emilia Galdiero Giovanna Donnarumma Giovanni Salerno Luisa de Martino 《FEMS microbiology letters》1996,145(2):167-172
Abstract Candida albicans yeast cells suspended in sterilized sea water and cultivated in Brain Heart Infusion broth were compared. Viability, chemical composition, surface hydrophobicity and ultrastructural characteristics showed variations after incubation in sea water. The yeast cells developed some ultrastructural changes after about a month in sea water. The surface hydrophobicity of the yeast cells was gradually reduced, starting from day 16, and continued to decline throughout the 32 days in sea water. A decrease in total carbohydrate, lipid and protein contents was also observed and corresponded with ultrastructural modifications. 相似文献
983.
Valeria Maida Federico Bennardini Francesco Bonomi Maria Luisa Ganadu Stefania Iametti Giovanni Maria Mura 《The protein journal》2000,19(4):311-318
Conformational modifications and changes in the aggregation state of human αB-crystallin were investigated at different concentrations of SDS, KBr, urea, and NH4SCN and at different temperatures. Intrinsic fluorescence measurements indicated complete and reversible unfolding of the protein at 2 M NH4SCN, whereas the concentration of urea required for complete and irreversible unfolding was 6 M. Gel permeation chromatography indicated almost complete dissociation of the micelle-like aggregate of αB-crystallin in 2 M NH4SCN, but only partial dissociation into large-sized aggregates in 6 M urea. Thiocyanate-treated αB-crystallin recovered its chaperone-like activity upon dilution of the dissociating agent, whereas the urea-treated protein did not. 相似文献
984.
Edoardo Fiorillo Valeria Orrú Stephanie M. Stanford Yingge Liu Mogjiborahman Salek Novella Rapini Aaron D. Schenone Patrizia Saccucci Lucia G. Delogu Federica Angelini Maria Luisa Manca Bitti Christian Schmedt Andrew C. Chan Oreste Acuto Nunzio Bottini 《The Journal of biological chemistry》2010,285(34):26506-26518
A missense C1858T single nucleotide polymorphism in the PTPN22 gene recently emerged as a major risk factor for human autoimmunity. PTPN22 encodes the lymphoid tyrosine phosphatase (LYP), which forms a complex with the kinase Csk and is a critical negative regulator of signaling through the T cell receptor. The C1858T single nucleotide polymorphism results in the LYP-R620W variation within the LYP-Csk interaction motif. LYP-W620 exhibits a greatly reduced interaction with Csk and is a gain-of-function inhibitor of signaling. Here we show that LYP constitutively interacts with its substrate Lck in a Csk-dependent manner. T cell receptor-induced phosphorylation of LYP by Lck on an inhibitory tyrosine residue releases tonic inhibition of signaling by LYP. The R620W variation disrupts the interaction between Lck and LYP, leading to reduced phosphorylation of LYP, which ultimately contributes to gain-of-function inhibition of T cell signaling. 相似文献
985.
Zalfa A. Abdel-Malek Ana Luisa Kadekaro Viki B. Swope 《Pigment cell & melanoma research》2010,23(2):171-186
Exposure to solar ultraviolet radiation (UV) is the main etiological factor for skin cancer, including melanoma. Cutaneous pigmentation, particularly eumelanin, afforded by melanocytes is the main photoprotective mechanism, as it prevents UV-induced DNA damage in the epidermis. Therefore, maintaining genomic stability of melanocytes is crucial for prevention of melanoma, as well as keratinocyte-derived basal and squamous cell carcinoma. A critical independent factor for preventing melanoma is DNA repair capacity. The response of melanocytes to UV is mediated mainly by a network of paracrine factors that not only activate melanogenesis, but also DNA repair, anti-oxidant, and survival pathways that are pivotal for maintenance of genomic stability and prevention of malignant transformation or apoptosis. However, little is known about the stress response of melanocytes to UV and the regulation of DNA repair pathways in melanocytes. Unraveling these mechanisms might lead to strategies to prevent melanoma, as well as non-melanoma skin cancer. 相似文献
986.
987.
Gary W. Daughdrill Pamela D. Vise Hongjun Zhou Xiaomin Yang Wen-Feng Yu Maria Luisa Tasayco 《Journal of biomolecular structure & dynamics》2013,31(5):663-670
Abstract The backbone dynamics of a partially folded, N-terminal fragment of E. coli thioredoxin were investigated using nuclear magnetic resonance spectroscopy (NMR). Relaxation data were collected at three temperatures and analyzed using reduced spectral density mapping. As temperature was increased, the values for the viscosity normalized J(0) and for J(ωH) increased, while J(ωN) decreased. The global trend observed for the viscosity normalized J(0) was consistent with an increase in the hydrodynamic volume of the fragment and suggested the presence of correlated rotational motion in the absence of long range interactions. In addition, the residue specific variation observed for the viscosity normalized J(0) suggested contributions to J(ω) from a range of correlation times that are close to the global correlation time. 相似文献
988.
Aspergillus terreus was transformed to hygromycin B resistance using a bacterial resistance gene under the control of Aspergillus nidulans regulatory sequences. Southern hybridization of transformants indicated that in most of the cases the vector DNA was integrated into the recipient chromosome in the form of tandem arrays. Transformants were mitotically stable in both selective and non-selective medium and retained their capacity to produce xylanase or glucoamylase activities. 相似文献
989.
990.