Simultaneous solving high-resolution structures of various enzymes from human kidney microsomes

Area of Science:

• Structural Biology
• Systems Biology
• Proteomics

Background:

• Traditional structural biology focuses on single biomacromolecules, limiting tissue-level investigation.
• An integrated systems biology approach for tissues was previously considered unattainable.

Purpose of the Study:

• To demonstrate the utility of cryo-electron microscopy (cryo-EM) for analyzing complex biological systems.
• To define the composition and structures of enzymes within a raw human kidney microsomal lysate.

Main Methods:

• Cryo-electron microscopy (cryo-EM) was applied to a raw human kidney microsomal lysate.
• Simultaneous identification and structural determination of multiple kidney enzymes were performed.

Main Results:

• Cryo-EM successfully defined the composition of the kidney lysate.
• Structures of four distinct kidney enzymes were solved.
• These enzymes are involved in protein biosynthesis, retinoic acid synthesis, carbohydrate metabolism, and amino acid regulation.

Conclusions:

• The four identified enzymes are linked to cellular processes implicated in diabetes onset and progression.
• Cryo-EM has significant potential for advancing tissue and organ proteomics at the atomic level.
• This study highlights a new era for structural biology in understanding complex biological systems.