蛋白质折叠 3D 路径图

一幅单面板 3D 科学插图，从左到右展示蛋白质折叠的四个阶段。阶段 1：多彩氨基酸珠子串（线框骨架），标注 「Primary structure」；阶段 2：粉色 α-螺旋与黄色 β-折叠，标注 「Secondary structure」；阶段 3：折叠成紧凑球形，半透明表面可见深紫疏水核，标注 「Tertiary structure」；阶段 4：两个球形亚基对称对接，标注 "Quaternary structure"。每个阶段置于薄玻璃台上，中灰色箭头连接。淡蓝色工作室背景，右上方柔和主光。9 pt 加粗无衬线标签。

A sequential 3D scientific illustration showing four stages of protein folding on a single panel, arranged left to right. Stage 1: a linear chain of amino acid beads (multi-coloured spheres on a backbone wire) labeled "Primary structure". Stage 2: the chain forming a pink alpha-helix coil and a yellow beta-sheet pleated ribbon, labeled "Secondary structure". Stage 3: the polypeptide folded into a compact globular shape with hydrophobic core (dark purple interior visible through semi-transparent surface), labeled "Tertiary structure". Stage 4: two identical globular subunits docking together symmetrically, labeled "Quaternary structure". Each stage sits on a thin glass platform. Connecting arrows between stages in mid-grey. Light-blue studio background with soft key light from upper right. Labels in 9 pt bold sans-serif below each stage. Minimal, science-publication quality.