Functions and behavior of a new type of ATPase(phosphatase) in halophytes

在盐生植物草莓中发现了一种新型的ATPase或磷酸酶。它以质膜结合和游离两种形式存在，其活性比为4/96。这两种形式的酶按以下顺序水解底物的磷酸酯：对硝基苯基磷酸盐；焦磷酸盐；ADP*ATP和GT；AMP。一价阳离子和二价阳离子对这两种酶的活性均有促进作用，而钼酸根和钒酸根离子对这两种酶的活性有较强的抑制作用。从这些性质来看，该酶应被认为是一种新型的酸性磷酸酶。这两种形式的酶都耐盐，特别是膜结合型受到高浓度盐的刺激。在非盐生植物、大豆和黄瓜中也发现了该酶，且随着植物耐盐性的增强，该酶呈浓度递增的分布。

A new type of ATPase or phosphatase was found in a halophyte, Solsola komaroli. It occurred in two forms of plasma membrane-bound and free, their activity ratio being 4/96. Both forms of the enzyme hydrolyzed phosphate ester of substrates in the following order ; p-nitrophenylphosphate > pyrophosphate > ADP * ATP > AMP. The activities of both enzymes were stimulated by mono- and di-valent cations, and they were strongly inhibited by molybdate and vanadate. From these properties, this enzyme should be accepted as a new type of acid phosphatase. Both forms of the enzyme were resistant to salinity, particularly the membrane-bound form was stimulated by high concentrations of salt. The present enzyme was also found in non-halophytes, soybean and cucumber, and it was distributed at an increasing concentration with an increase in salt tolerance of plants.