タンパク質のPEG化は安定性を向上することが知られているが，反応制御は難しく，複数の修飾異性体が生成する．これらの修飾体の分離には，イオン交換クロマトグラフィー（IEC）が用いられる．タンパク質に対して構築されたIECの分離機構モデルをPEG化タンパク質に適用することができれば，分離条件を合理的に決定可能となる．このためmono-PEG修飾体としてPEG化BSAを，random-PEG修飾体としてPEG化lysozymeを用い，それらの溶出時の塩濃度勾配と溶出塩濃度を，機構モデルを用いて解析した．いずれのPEG修飾体においてもモデルの適用が可能であり，担体上の結合部位の数は未修飾のものとほぼ同じ値をとることがわかった．また，機構モデルから算出される分配係数に基づき，移動相塩濃度を設定すると，PEG化と同時にカラムから反応生成物を脱離させることや，リサイクル型の連続反応分離操作も可能で...

Amino-terminal acetylation is a ubiquitous protein modification affecting the majority of eukaryote proteins to regulate stability and function. We describe an optimised recombinant expression system for rapid production of amino terminal-acetylated proteins within bacteria. We go on to describe the system's use in a fluorescence based in vivo assay for use in the high-throughput screen to iden...

BACKGROUND The degradation of DNA represents one of the main issues in the genetic analysis of archeological specimens. In the recent years, a particular kind of post-mortem DNA modification giving rise to nucleotide misincorporation ("miscoding lesions") has been the object of extensive investigations. METHODOLOGY/PRINCIPAL FINDINGS To improve our knowledge regarding the nature and incidence...

We have been studying the evolution and function of DNA methylation in vertebrate animals using three related approaches. The first is to further characterise proteins that bind to methylated DNA. Such proteins can be viewed as 'receptors' of the methyl-CpG 'ligand' that mediate downstream consequences of DNA modification. The second approach involves CpG islands. These patches of non-methylate...

The purpose of this study was to identify Iranian EFL learner’s awareness degree of listening factors and strategies and the effect of input modification in improvement of listening comprehension. Since listening is a mental process and is not directly observable I had used qualitative method and sought to subjective data not objective one. Two groups of boys and girls in intermediate level had...