Hyperthermophiles, a subset of prokaryotes that thrive in adverse temperatures, potentially utilize the protein molecular biosystem for maintaining thermostability in a wide range of temperatures. Recent studies revealed that these organisms have smaller proportions of intrinsically disordered proteins. In this study, we performed sequence and structural analysis to investigate the maintenance of protein conformation and their stability at different temperatures. The sequence analysis reveals the higher proportion of charged amino acids are responsible for preventing the helix formation and, hence, become disordered regions. For structural analysis, we chose shikimate dehydrogenase from four species, namely Listeria monocytogenes, Escherichia coli, Thermus thermophilus, and Methanopyrus kandleri, and evaluated the protein adaptation at 283 K, 300 K, and 395 K temperatures. From this investigation, we found more residues of shikimate dehydrogenase prefer an order-to-disorder transition at 395 K only for hyperthermophilic species. The solvent-accessible surface area (SASA) and hydrogen-bond analysis revealed that the tertiary conformation and the number of hydrogen bonds for hyperthermophilic shikimate dehydrogenase are highly preserved at 395 K, compared to 300 K. Our simulation results conjointly provide shikimate dehydrogenase of hyperthermophile which resists high temperatures through stronger protein tertiary conformations.

嗜热菌是在不利温度下生长旺盛的原核生物的子集，可能利用蛋白质分子生物系统在较宽的温度范围内保持热稳定性。最近的研究表明，这些生物体内固有紊乱的蛋白质比例较小。在这项研究中，我们进行了序列和结构分析，以研究蛋白质构象的维持及其在不同温度下的稳定性。序列分析表明，较高比例的带电荷氨基酸负责阻止螺旋的形成，因此成为无序区域。为了进行结构分析，我们从四种物种中选择了sh草酸脱氢酶，即单核细胞增生性李斯特菌，大肠杆菌，嗜热栖​​热菌和Methanopyrus kandleri，并评估了蛋白质在283 K，300 K和395 K温度下的适应性。从这项调查中，我们发现更多的of草酸脱氢酶残基仅对高度嗜热菌种更喜欢在395 K上从有序到无序的转变。溶剂可及的表面积（SASA）和氢键分析表明，在395 K时，与300 K相比，高嗜热the草酸脱氢酶的叔构象和氢键数得到了高度保留。我们的模拟结果共同提供了超嗜热菌的sh草酸脱氢酶通过更强的蛋白质三级构象抵抗高温。