Characterization of Putative a (1,3)-β-D-glucan (curdlan) Synthase for a Low Molecular Weight Curdlan Biosynthesis from Agrobacterium sp. M503

2013 ◽  
Vol 807-809 ◽  
pp. 2031-2034
Author(s):  
Yu Mei Li ◽  
Qiang Li ◽  
Sheng Han ◽  
Dong Xue Song ◽  
Yan Hong Qu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Random Coil ◽  
Low Molecular Weight ◽  
Base Pairs ◽  
Reading Frame ◽  
Coil Structure ◽  
Α Helix ◽  
Encoding Protein ◽  
Β Sheet

A β-(1,3)-D-glucan (curdlan) synthase gene for a low molecular weight curdlan biosynthesis, crdSAg, from Agrobacterium sp. M503 was cloned and its encoding protein was characterized by several online protein analysis softwares. The crdSAg consists of 1965-base-pairs Open Reading Frame (ORF) encoding a protein with molecular weight approximate 73.5 kDa, which contains the conserved domain of CESA-CelA_like belonging to glycosyltransferase family 2 (GT2). Moreover, CrdSAg was a membrane protein with seven hydrophobic transmembrance domains. The second structure analysis indicated it was composed of 43.12% α-helix, 17.89% β-sheet, and 38.99% random coil structure. These data will lay a foundation to clarify the biosynthesis mechanism of the low molecular weight curdlan.

Influence of Post-Treatment with Methanol Vapor on the Properties of SF/P(LLA-CL) Nanofibrous Scaffolds

2011 ◽  
Vol 236-238 ◽  
pp. 2221-2224
Author(s):  
Kui Hua Zhang ◽  
Xiu Mei Mo
Keyword(s):  
Electrospun Nanofibers ◽  
Random Coil ◽  
Methanol Vapor ◽  
Nanofibrous Scaffolds ◽  
Nanofibrous Structure ◽  
Α Helix ◽  
Β Sheet ◽  
Ideal Method ◽  
C Nmr

In order to improve water-resistant ability silk fibroin (SF) and SF/P(LLA-CL) blended nanofibrous scaffolds for tissue engineering applications, methanol vapor were used to treat electrospun nanofibers. SEM indicated SF and SF/ P(LLA-CL) scaffolds maintained nanofibrous structure after treated with methanol vapor and possessed good water-resistant ability. Characterization of 13C NMR clarified methanol vapor induced SF conformation from random coil or α- helix to β-sheet. Moreover, treated SF/ P (LLA-CL) nanofibrous scaffolds still kept good mechanical properties. Methanol vapor could be ideal method to treat SF and SF/ P(LLA-CL) nanofibrous scaffolds for biomedical applications.

Cloning of the Key Succinoglycan Biosynthesis Gene exoA and exoY from Agrobacterium sp. M-503 and the Sequence Analysis of Encoding Proteins

2013 ◽  
Vol 807-809 ◽  
pp. 2027-2030
Author(s):  
Ying Zi Liu ◽  
Qiang Li ◽  
Qing Hua Wang ◽  
Yu Mei Li ◽  
Yan Hong Qu ◽  
...  
Keyword(s):  
Structure Prediction ◽  
3D Structure ◽  
Random Coil ◽  
High Molecular Weight Polymer ◽  
Molecular Weight Polymer ◽  
Reading Frame ◽  
Molecular Weights ◽  
Biosynthesis Gene ◽  
Α Helix ◽  
Β Sheet

Succinoglycan is an acidic exopolysaccharide that is important for invasion of the nodules. It is a high-molecular-weight polymer consisting of repeating octasaccharide units. These units are synthesized by a complex pathway encoded by numbers of exo genes. In this study, two key genes,exoAandexoY, were cloned and sequenced, which controlled the first two glycosyltransferase reactions in the biosynthesis of succinoglycan. The sequences contained 999-base-pares (bp) and 681-bp Open reading Frame (ORF) encoding 332 and 236 amino-acid proteins with molecular weights of approximate 36.8 kDa and 25.5 kDa , respectively. The putative proteins, ExoA and ExoY, were analyzed by several online protein analysis softwares. The results showed ExoA and ExoY were the membrane proteins with three (ExoA) and one (ExoY) hydrophobic transmembrance domains. Their theoretical PI values were 9.49 and 9.34, respectively. The second structures analysis indicated that they were composed of 45.48% and 38.94% α-helix, 13.55% and 16.81% β-sheet, and 40.96% and 44.25% random coil structures respectively. These data will lay a foundation for the subsequent 3D structure prediction and gene mutation to improve succinoglycan production.

13C CP/MAS NMR Spectroscopic Characterization of Native Silk Fibers

2011 ◽  
Vol 175-176 ◽  
pp. 328-332 ◽  
Author(s):  
Wei Zhang ◽  
Jian Xin He ◽  
Yan Wang
Keyword(s):  
13C Nmr Spectroscopy ◽  
Spectroscopic Characterization ◽  
Random Coil ◽  
Silk Fibers ◽  
Significant Difference ◽  
Sheet Structure ◽  
Α Helix ◽  
Cp Mas Nmr ◽  
Β Sheet

Differences in secondary structure among Bombyx mori (B. mori) silk and two wild silks of Antheraea yamamai (A. yamamai) and Antheraea pernyi (A. pernyi) were investigated by CP/MAS 13C NMR Spectroscopy. The β-sheet structure was primary in three silk, and B. mori silk had the highest β-sheet structure. Although amino acid compositions are very similar for two wild silk, their secondary structures had significant difference. A. yamamai silk contained more α-helix structure, whereas more β-turn and random coil structures formed in A. pernyi silk. B. mori silk was mainly composed of anti-parallel β-sheet structure, however, the parallel β-sheet structure was advantage in the two wild silks, and A. yamamai silk contained more anti-parallel β-sheet conformation than A. pernyi silk.

Preparation and Characterization of Wool Keratin/PVA Blended Films

2011 ◽  
Vol 175-176 ◽  
pp. 132-136 ◽  
Author(s):  
Ming Xia Gou ◽  
Xu Hong Yang
Keyword(s):  
Aqueous Solution ◽  
Random Coil ◽  
Ftir Analysis ◽  
Microscopy Investigation ◽  
Electron Microscopy Investigation ◽  
Scanning Electron Microscopy Investigation ◽  
Α Helix ◽  
Β Sheet ◽  
Wool Keratin

The method of extracting protein from wool was studied for the purpose of reusing the waste wool. The aqueous solution of wool keratin was prepared with Sodium Shlfide as reductive agent. In this paper, PVA was used to mix with keratin in different proportions. Both solutions were cast to obtain blended films. Scanning electron microscopy investigation showed that the surface of blended films was rough and uneven and the surface of the pure keratin film had small peridiole. FTIR analysis indicated that the secondary structure of the keratin was influenced by the blending ratios. Compared with wool fiber, the keratin film cast from aqueous solution showed a decrease in the amount of α-helix structure, while β-sheet and random coil conformations increased. When the keratin solution and PVA solution were blended in the ratios of 40:60, the film was flexible and rigid, and had good mechanical properties. This study encourages the further investigation of the applications of wool keratin films in the biomedical field, which could provide a new way to reuse various waste feathers.

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