Abstract
Homoacetogenic bacteria have received attention as a hydrogenotrophic population that offers a significant energetic advantage to the host animal. Reductive acetogenesis is likely an important hydrogen disposal mechanism in the cecum of rabbits. However, molecular ecology information about cecal acetogen candidates has rarely been reported. To better understand the effect of host selection in the rabbit cecal acetogen community with respect to growth, rabbits at four different age stages (30, 60, 120 and 180 days) with the same diet were studied. Although the abundance of potential acetogens and methanogens was high in the cecum of rabbits undergoing growth, many novel potential acetogen populations were observed in the cecum of rabbits across all age groups. Young and adult rabbits had their own distinct acetogen community although they received the same diet, which suggests that as the rabbit ages, acetogens in the cecum undergo developmental changes because of host selection that are independent of diet, and perhaps the different acetogen communities result in different hydrogenotrophic characteristics. The within-group similarity increased with age, indicating that the acetogen community converges to a more homogeneous and stable arrangement with aging.
Highlights
Homoacetogenic bacteria are a group of obligate anaerobic bacteria that utilize the acetyl coenzyme-A (CoA) pathway to synthesize acetate from syngas [1]
The total volatile fatty acids (VFA) and ammonia nitrate decreased with age (Table 2)
The primary activity of the bacterial population that resides in the hindgut is fermentation, and the major products are VFA
Summary
Homoacetogenic bacteria (acetogens) are a group of obligate anaerobic bacteria that utilize the acetyl coenzyme-A (CoA) pathway to synthesize acetate from syngas [1]. 1013 kg of acetate is formed annually in anaerobic habitats [2]. Acetogens are phylogenetically quite diverse and metabolically versatile [3, 4], but only some strains, such as Moorella thermoacetica [5, 6], Clostridium ljungdahlii [7, 8], Clostridium ragsdalei [8, 9] and their genetic modifications, are used in syngas fermentation for biofuels. Homoacetogenesis is a promising pathway to compete with methanogens in the rumen, because methane producers cause 23% of the global anthropogenic methane emissions [10]. A better understanding of the molecular ecology of the acetogen population will help develop new acetogen products and enhance its catalyst function
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
