title: Mycobacterium gastri
text: # Mycobacterium gastri
  
  Mycobacterium gastri is a species of the phylum Actinomycetota (Gram-positive bacteria with high guanine and cytosine content, one of the dominant phyla of all bacteria), belonging to the genus Mycobacterium.
  
  ## Description
  
  Moderately long to long, Gram-positive, aerobic, nonmotile and acid-fast rods.
  
  Colony characteristics
  
  * Nonchromogenic, smooth to rough, white colonies on Löwenstein-Jensen medium and smooth or somewhat granular on Middlebrook 7H10 agar.
  
  Physiology
  
  * Growth on Löwenstein-Jensen medium or on Middlebrook 7H10 agar at 37 °C, (temperature range 25 °C-40 °C), within 7 or more days.
  * Does not grow in the presence of ethambutol or isoniazid.
  
  Differential characteristics
  
  * Closely related to M. kansasii
  * M. gastri and M. kansasii share an identical 16S rDNA sequence. Species differentiation is possible by differences in the ITS and hsp65 sequences.
  * M. kansasii produces a photochromogenic yellow pigment.
  * AccuProbes for M. kansasii are negative.
  
  ## Pathogenesis
  
  * Casual resident of human stomachs, but not considered a cause of disease.
  * Biosafety level 1
  
  ## Type strain
  
  * First isolated from human gastric specimen. Also found in soil.
  
  Strain ATCC 15754 = CCUG 20995 = CIP 104530 = DSM 43505 = JCM 12407.
  
  