Related Experiment Video

Updated: Oct 2, 2026

Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source
06:37

Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source

Published on: February 7, 2013

Reduced hemoglobin as an inhibitor of human polymorphonuclear leukocyte bacterial killing. Role of hemoglobin--oxygen

W D Welch, D M Rose, R Carlson

    Surgery
    |January 1, 1982
    PubMed

    The effect of reduced hemoglobin (Hb) on in vitro human polymorphonuclear leukocyte (PMNL) bactericidal activity was investigated. Addition of Hb at physiologic concentrations and oxygen partial pressures (150 mg/ml, 35 torr) to PMNL bactericidal assays significantly inhibited the killing of blood culture isolates of Escherichia and Staphylococcus aureus. Raising the oxygen partial pressure above 35 torr greatly decreased this inhibition. Carboxy hemoglobin, produced by equilibrium of Hg with carbon monoxide, is unable to bind oxygen and did not inhibit PMNL bactericidal killing. We postulate that reduced Hb may scavenge oxygen near the surface of the PMNL therapy preventing utilization of oxygen by PMNL for maximal bactericidal activity.

    More Related Videos

    Measurement of Heme Synthesis Levels in Mammalian Cells09:43

    Measurement of Heme Synthesis Levels in Mammalian Cells

    Published on: July 9, 2015

    Fast and Specific Assessment of the Halogenating Peroxidase Activity in Leukocyte-enriched Blood Samples05:17

    Fast and Specific Assessment of the Halogenating Peroxidase Activity in Leukocyte-enriched Blood Samples

    Published on: July 28, 2016

    Related Concept Videos

    Factors Affecting Respiration01:24

    Factors Affecting Respiration

    Respiration is a crucial physiological function involving exchanging oxygen (O2) and carbon dioxide (CO2) between an organism and its environment. Various factors can impact this essential process:
    Role of Hematopoietic Growth Factors01:28

    Role of Hematopoietic Growth Factors

    Hematopoietic growth factors are molecules that regulate the differentiation rate of hematopoietic stem cells (HSCs). Erythropoietin (EPO), primarily produced by the kidneys, plays a crucial role in erythrocyte production. When oxygen levels in the blood are low, EPO is released into the bloodstream, reaching the bone marrow, where it stimulates HSCs to differentiate and mature into erythrocytes, which are vital for oxygen transport.
    Thrombopoietin (TPO), mainly released by the liver,...
    Hemoglobin01:24

    Hemoglobin

    Hemoglobin is a globular protein made up of four subunits. Two of these subunits are alpha chains, and the other two are beta chains. Each subunit contains a molecule of heme, which has an iron atom and can bind to oxygen. When an oxygen molecule binds to one heme group, it changes the shape of hemoglobin, making it easier for the other heme groups to bind oxygen as well.
    When all four heme groups are bound to oxygen, the resulting molecule is called oxyhemoglobin. As a result, arterial blood...
    Disorders of Erythrocytes01:27

    Disorders of Erythrocytes

    Disorders of erythrocytes, or red blood cells (RBCs), include a range of conditions affecting their number, shape, or function.
    Erythrocyte disorders can be broadly categorized into two main types: anemic and polycythemic conditions.
    A low oxygen-carrying capacity of the blood due to the loss, lower production, or destruction of erythrocytes is termed anemia. Hemorrhagic anemia, for example, occurs when bleeding from an external wound or internal ulcer reduces erythrocyte counts.
    On the other...
    Antimicrobial Proteins01:23

    Antimicrobial Proteins

    Antimicrobial proteins are important components of the immune system. They aid the body in combating pathogens by either killing them directly or hindering their replication processes. Four main types of antimicrobial substances are interferons, the complement system, iron-binding proteins, and antimicrobial proteins.
    Interferons
    Interferons (IFNs) are proteins produced by lymphocytes, macrophages, and fibroblasts infected with viruses. While IFNs cannot prevent viruses from entering and...
    Factors Affecting Erythropoiesis01:24

    Factors Affecting Erythropoiesis

    The cardiovascular system regulates the number of erythrocytes in the bloodstream to ensure optimal oxygen transport. It also prevents over-proliferation of these cells, which helps to maintain blood viscosity and flow rate.
    Several factors influence the erythrocyte production rate, with tissue oxygen level being among the most critical. Intense exercise or high altitudes can cause tissue hypoxia, which triggers the kidneys to release more erythropoietin (EPO) into the bloodstream.
    EPO then...