Is hemolytic streptococcus Gram-positive or Gram-negative?
Dec 02, 2025
Source: Cainiu Health
Dr. Gao Jun
Introduction
Under normal circumstances, hemolytic streptococci are Gram-positive bacteria. Maintaining a clean and dry environment can reduce bacterial growth. Wash hands frequently with running water and soap, and avoid touching mucosal areas such as the mouth and nose with hands. Clothes and bedding should be cleaned and sun-dried regularly; especially undergarments should be washed separately. A balanced diet helps enhance the body's resistance.
Under normal circumstances, hemolytic streptococci belong to Gram-positive bacteria. The detailed analysis is as follows:
Hemolytic streptococci are classified as Gram-positive bacteria primarily due to their cell wall structure and reaction characteristics in Gram staining. These bacteria have a thick and densely cross-linked peptidoglycan layer in their cell walls and lack lipopolysaccharide components. During Gram staining, crystal violet dye penetrates deeply into the peptidoglycan layer and is fixed by iodine solution; subsequent alcohol decolorization cannot wash it out, resulting in a purple appearance—consistent with the staining characteristics of Gram-positive bacteria. This feature also determines important biological properties such as their pathogenic mechanisms and sensitivity to antibiotics.
To reduce bacterial growth, maintain clean and dry environments. Wash hands frequently with running water and soap, and avoid touching mucosal areas such as the mouth and nose with hands. Regularly wash and sun-dry clothes and bedding, and wash undergarments separately. Maintain a balanced diet to enhance bodily resistance, avoid crowded places with poor ventilation, and promptly clean and disinfect any skin wounds to prevent bacterial invasion and subsequent infection.
