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Síntesis de vitamina B12 por las bacterias del intestino delgado humano
Nature
|February 21, 1980
Resumen
La absorción de la vitamina B12 (cianocobalamina) ocurre en el íleon. Las bacterias en el intestino delgado, como Pseudomonas y Klebsiella, pueden sintetizar cantidades significativas de vitamina B12.
Área de la Ciencia:
- Microbiología Microbiología.
- Fisiología Humana Fisiología Humana.
- Ciencias de la Nutrición Ciencias de la Nutrición
Sus antecedentes:
- La vitamina B12 (ciancobalamina) se absorbe principalmente en el íleon a través del factor intrínseco.
- Las heces humanas contienen vitamina B12 producida por las bacterias del colon, pero es inaccesible para los humanos.
- El intestino delgado humano alberga microflora, particularmente en las poblaciones del sur de la India.
Objetivo del estudio:
- Para investigar el potencial de las bacterias del intestino delgado para sintetizar la vitamina B12 en los seres humanos.
- Para identificar especies bacterianas específicas en el intestino delgado capaces de la síntesis de vitamina B12.
Principales métodos:
- Análisis de la microflora del intestino delgado.
- Identificación de las especies bacterianas presentes en el intestino delgado.
- Evaluación de las capacidades de síntesis de vitamina B12 de grupos bacterianos identificados.
Principales resultados:
- Se observó una síntesis significativa de vitamina B12 en el intestino delgado.
- Se identificaron especies de Pseudomonas y Klebsiella como productores clave de vitamina B12 en el intestino delgado.
Conclusiones:
- El intestino delgado humano alberga bacterias, incluidas Pseudomonas y Klebsiella, que pueden sintetizar cantidades significativas de vitamina B12.
- Este hallazgo sugiere una posible fuente endógena de vitamina B12 dentro del intestino delgado, lo que desafía las suposiciones anteriores sobre su absorción y disponibilidad.
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