A gene encoding creatine kinase was identified in two cryptosporidia species, Cryptosporidium muris and C. andersonii. They were syntenic and shared 91% identity 94% identity at the amino acid level and nucleotide levels respectively. The C. muris creatine kinase was characterized biochemically and shown to phosphorylate both creatine and glycocyamine with a 20-fold greater preference for creatine. The observed catalytic turnover with creatine was k_cat = 30 s⁻¹ with a catalytic efficiency of 15.4 mM⁻¹ s⁻¹. These values were within the range observed for other creatine kinases. A search of all the apicomplexa genomes available on EuPathDB did not reveal any other phosphagen kinase genes raising the possibility of horizontal gene transfer. However, no definitive conclusion could be drawn regarding this hypothesis given the massive amount of gene loss in the apicomplexa species which are primarily parasitic species. The implications of a creatine kinase in the parasites' infection cycle are discussed.

在两个隐孢子虫种类中发现了编码肌酸激酶的基因，即隐孢子虫和C. andersonii。它们是同系的，分别在氨基酸水平和核苷酸水平上具有91％的一致性，94％的一致性。所述C.缪里斯肌酸激酶生化表征和示出为具有用于肌酸20倍更高的优选磷酸化两者肌酸和胍基乙酸。观察到的肌酸催化转化率为k _cat  = 30 s ^-1，催化效率为15.4 mM ^-1  s ^-1。这些值在其他肌酸激酶观察到的范围内。对EuPathDB上所有可用的apicomplexa基因组进行的搜索均未发现任何其他磷酸酶激酶基因，从而增加了水平基因转移的可能性。然而，鉴于在主要是寄生虫的双复合菌种中大量的基因损失，关于这一假设尚无定论。讨论了肌酸激酶在寄生虫感染周期中的意义。