ニトロゲナーゼ 化学特性,用途語,生産方法
性質
窒素固定酵素.ATPの加水分解に共役してN2 を2NH3 に還元.成分1はN2還元酵素の本体でα2β2 構造,[4Fe-3S],FeMo補因子の [Mo-7Fe-9S]クラスター,ホモクエン酸をもつ.成分2は成分1を還元する酵素で二量体あたり1[4Fe-4S]をもち,FeMo補因子の合成にも関与.O2 で失活
解説
窒素分子をATP存在下でアンモニアに還元し,1分子の水素を生成する酵素.窒素分子を唯一の窒素源として生育できる微生物がこの酵素を有する.活性中心には鉄とモリブデンを有する金属酵素である.
説明
The biological catalyst that reduces atmospheric N2
to ammonia is the metalloenzyme nitrogenase which exists in three genetically distinct forms: the conventional
Mo-based system, Mo-nitrogenase, and two more
recently discovered alternative systems, V-nitrogenase
and nitrogenase-3. As early as 1930 (81) molybdenum,
Mo, was believed to be absolutely essential for nitrogen
fixation, even though vanadium, V, was found to be almost
as stimulatory to bacterial growth on N2 (82). The requirement
for Mo was solidified both by the isolation of the
larger of the two component proteins of nitrogenase, the
molybdenum–iron, MoFe, protein (83) having a FeMocofactor
(84), and later by the discovery of nitrogen-fixation
specific (nif) genes involved in Mo-specific functions.
天然物の起源
MoFeプロテイン(成分1),α鎖:2~534, β鎖:2~458Feプロテイン(成分2):2~273
定義
Enzyme that fixes nitrogen and can
be isolated from soil bacteria. It is possible to synthesize ammonia from nitrogen and hydrogen without high temperatures and pressures by means of
nitrogenase. Pyruvic acid is an adjunct of the reaction.
农业用途
The enzyme nitrogenase fixes inert nitrogen in soils. It
lowers the activation energy required for the conversion
of nitrogen (N) to ammonia (NH
3 ).Nitrogen fixation by microorganisms
can be symbiotic and non-symbiotic.
The nitrogenase enzyme complex consists of two
proteins. The first is a larger molybdenum-iron protein of
2 to 2.7 x10
5 molecular weight, containing 1 or 2 atom
of molybdenum, 17 to 36 atoms of iron and 14 to 28 acid
labile sulphur atoms. The second is an iron-protein
molecule of 55 to 67 x 10
3 molecular weight, containing
four atoms each of iron and acid labile sulphur.
ニトロゲナーゼ 上流と下流の製品情報
原材料
準備製品