Department of Biology, College of Science, University of Hail, Hail, Saudi Arabia.
InnovAAte Pty Ltd, Newcastle, NSW, Australia.
Biomol Biomed. 2023 Nov 3;23(6):1038-1050. doi: 10.17305/bb.2023.9246.
Staphylococcus aureus strains are a great contributor to both hospital acquired infections as well as community acquired infections. The objective of the present investigation was to compare potential differences in cytoplasmic amino acid levels between clinical and ATCC 29213 strains of S. aureus. The two strains were grown under ideal conditions to mid-exponential and stationary growth phases, after which they were harvested to analyze their amino acid profiles. Initially, the amino acid patterns of both strains were compared at the mid-exponential phase when grown in controlled conditions. At the mid-exponential phase, both strains shared common features in cytoplasmic amino acid levels, with glutamic acid, aspartic acid, proline, and alanine identified as key amino acids. However, the concentration profiles of seven amino acids exhibited major variances between the strains, even though the total cytoplasmic levels of amino acids did not alter significantly. At the stationary phase, the magnitudes of the amino acids abundant in the mid-exponential phase were altered. Aspartic acid became the most abundant amino acid in both strains accounting for 44% and 59% of the total amino acids in the clinical and ATCC 29213 strains, respectively. Lysine was the second most abundant amino acid in both strains, accounting for 16% of the total cytoplasmic amino acids, followed by glutamic acid, the concentration of which was significantly higher in the clinical strain than in the ATCC 29213 strain. Interestingly, histidine was clearly present in the clinical strain but was virtually lacking in the ATCC 29213 strain. This study reveals the dynamic diversity of amino acid levels among strains, which is an essential step toward illustrating the variability in S. aureus cytoplasmic amino acid profiles and could be significant in explaining variances among strains of S. aureus.
金黄色葡萄球菌菌株是医院获得性感染和社区获得性感染的主要病原体。本研究旨在比较临床分离株和 ATCC29213 金黄色葡萄球菌菌株细胞质氨基酸水平的潜在差异。将两株菌在理想条件下培养至指数中期和稳定期，然后收获进行氨基酸谱分析。首先，在受控条件下生长的指数中期比较两株菌的氨基酸模式。在指数中期，两株菌的细胞质氨基酸水平具有共同特征，谷氨酸、天冬氨酸、脯氨酸和丙氨酸被鉴定为关键氨基酸。然而，即使总细胞质氨基酸水平没有显著变化，两种菌株之间的 7 种氨基酸浓度谱仍存在较大差异。在稳定期，指数中期丰富的氨基酸的幅度发生了变化。天冬氨酸成为两株菌中最丰富的氨基酸，分别占临床株和 ATCC29213 株总氨基酸的 44%和 59%。赖氨酸是两株菌中第二丰富的氨基酸，占总细胞质氨基酸的 16%，其次是谷氨酸，其浓度在临床株中明显高于 ATCC29213 株。有趣的是，组氨酸在临床株中明显存在，但在 ATCC29213 株中几乎不存在。本研究揭示了菌株间氨基酸水平的动态多样性，这是阐明金黄色葡萄球菌细胞质氨基酸谱变异性的重要步骤，可能对解释金黄色葡萄球菌菌株间的差异具有重要意义。
