Microbe Identification
Microbe nameHaemophilus influenzae
NCBI Taxonomy ID727
DescriptionHaemophilus influenzae, a Gram-negative, non-motile, rod-shaped bacterium, thrives at a temperature range of 22-37°C, falling under the category of mesophilic microbes. As a heterotroph, it derives energy by breaking down complex organic molecules, primarily carbon-rich compounds, and converting them into ATP. Haemophilus influenzae produces energy through a process called fermentation, utilizing the byproducts of glycolysis to generate ATP. The Gram stain reaction yields a pinkish-red color, indicating the presence of a thin peptidoglycan layer, characteristic of Gram-negative bacteria. The organism's rod shape is typical of the family Pasteurellaceae, to which Haemophilus influenzae belongs. Haemophilus influenzae is a facultative anaerobe, able to survive in the presence or absence of oxygen. However, it grows more readily in aerobic conditions, with optimal growth occurring between 25-30°C. Its ability to adapt to different environmental conditions makes it a versatile and opportunistic pathogen. As a ubiquitous organism, Haemophilus influenzae can be found in various body sites, including the nasopharynx, throat, sinuses, and middle ear, as well as on the skin, conjunctiva, and respiratory tract. It is not limited to humans, as it also infects other mammals, including animals and livestock. Haemophilus influenzae has been identified as a significant pathogen, responsible for a range of diseases, including meningitis, pneumonia, otitis media, and conjunctivitis. Its ability to adhere to host cells and evade the host immune response contributes to its virulence.
Microbe Taxonomy
SuperkingdomBacteria
KingdomEubacteria
PhylumProteobacteria
ClassGammaproteobacteria
OrderPasteurellales
FamilyPasteurellaceae
GenusHaemophilus
Species influenzae
Microbe Properties
Gram staining propertiesNegative
ShapeBacilli
MobilityNo
Flagellar presenceNo
Number of membranes2
Oxygen preferenceFacultative anaerobe
Optimal temperature35
Temperature rangeMesophilic
HabitatHostAssociated
Biotic relationshipFree living
Cell arrangementNot Available
SporulationNot Available
MetabolismSaccharolytic, fermentative
Energy sourceNot Available
Host and Biospecimens
HostBody siteBiospecimenData SourceReference
HumanHuman Oral Microbiome Database (HOMD)20624719
HumanBronchiBacDive34718743
HumanPharynxBacDive34718743
HumanLower respiratory tractBacDive34718743
HumanUpper respiratort tractBacDive34718743
HumanStomachBacDive34718743
HumanNasopharynxBacDive34718743
HumanTracheaBacDive34718743
HumanOral cavityBacDive34718743
HumanSinusBacDive34718743
HumanLungDisbiome27388563
HumanLungSputumDisbiome29579057
HumanNasopharynxDisbiome26492486