CAJ | 학술논문

亚碲酸盐是碲的一含氧阴离子，其对微生物具高度毒性．在许多的致病菌内已经鉴定出数个抗亚碲酸盐基因(terZABCDEF)．之前，作者解出抗亚碲酸盐蛋白质TerD液体核磁共振结构并指出在细菌内TerD可能是一钙离子传感器．TerZ与TerD在序列上有40%相同性，其包括了一额外的9氨基酸片段L36-N44，并且显示出非常弱的钙离子亲合性．有趣的是，少了额外片段的TerZdel拥有与TerD可比较的钙离子亲合性．根据化学位移指数及同源模拟结果，此额外片段为一无二级结构且延伸的loop，可能扰乱钙离子结合位置的构形，同时也阻碍了钙离子接近其结合位置，因此大大降低钙离子亲合性．
아제산염시제적일함양음리자，기대미생물구고도독성．재허다적치병균내이경감정출수개항아제산염기인(terZABCDEF)．지전，작자해출항아제산염단백질TerD액체핵자공진결구병지출재세균내TerD가능시일개리자전감기．TerZ여TerD재서렬상유40%상동성，기포괄료일액외적9안기산편단L36-N44，병차현시출비상약적개리자친합성．유취적시，소료액외편단적TerZdel옹유여TerD가비교적개리자친합성．근거화학위이지수급동원모의결과，차액외편단위일무이급결구차연신적loop，가능우란개리자결합위치적구형，동시야조애료개리자접근기결합위치，인차대대강저개리자친합성．
Tellurite (TeO32–), an oxyanion of tellurium, is highly toxic to most microorganisms. Several tellurite resistance genes (terZABCDEF) have been identified in many pathogenic bacteria. Previously, we determined the NMR solution structure of the tellurite resistance protein TerD and suggested that TerD may function as a calcium sensor in bacteria. TerZ, which shares 40% sequence identity with TerD, contains an extra 9-residue segment of L36FGSIFGGN44 and exhibits much weaker Ca2+-binding affinity. Interestingly, TerZdel in which the extra segment is deleted has comparable binding affinity to TerD. Based on chemical shift index and homology modeling results, it was revealed that the extra segment is unstructured and forms an extended loop, which may disturb the conformation of Ca2+-binding sites and also prevent Ca2+ from contacting its binding site, hence significantly reduce Ca2+-binding affinity.