Berkelman T, Garret-Engele P, Hoffman N E
Department of Plant Biology, Carnegie Institution of Washington, Stanford, California 94305.
J Bacteriol. 1994 Jul;176(14):4430-6. doi: 10.1128/jb.176.14.4430-4436.1994.
An ATP-dependent Ca2+ uptake activity was identified in plasma membrane vesicles prepared from Synechococcus sp. strain PCC 7942. This activity was insensitive to agents which collapse pH gradients and membrane potentials but sensitive to vanadate, indicating that the activity is catalyzed by a P-type Ca(2+)-ATPase. A gene was cloned from Synechococcus sp. strain PCC 7942 by using a degenerate oligonucleotide based on a sequence conserved among P-type ATPases. This gene (pacL) encodes a product similar in structure to eukaryotic Ca(2+)-ATPases. We have shown that pacL encodes a Ca(2+)-ATPase by demonstrating that a strain in which pacL is disrupted has no Ca(2+)-ATPase activity associated with its plasma membrane. In addition, Ca(2+)-ATPase activity was restored to the delta pacL strain by introducing pacL into a second site in the Synechococcus sp. strain PCC 7942 chromosome.
在从聚球藻属（Synechococcus sp.）菌株PCC 7942制备的质膜囊泡中鉴定出一种依赖ATP的Ca2+摄取活性。该活性对能消除pH梯度和膜电位的试剂不敏感，但对钒酸盐敏感，这表明该活性是由一种P型Ca(2+)-ATP酶催化的。通过使用基于P型ATP酶中保守序列的简并寡核苷酸，从聚球藻属菌株PCC 7942中克隆了一个基因。该基因（pacL）编码的产物在结构上与真核生物Ca(2+)-ATP酶相似。我们通过证明pacL被破坏的菌株其质膜没有Ca(2+)-ATP酶活性，表明pacL编码一种Ca(2+)-ATP酶。此外，通过将pacL引入聚球藻属菌株PCC 7942染色体的第二个位点，Ca(2+)-ATP酶活性恢复到了缺失pacL的菌株中。
