The genus Paenibacillus includes bacteria which are facultative anaerobic and endospore-forming.
Moreover, it has been suggested that PCRBs, which are facultative anaerobes, and other microbes, use Clds for metabolisms in anoxia.
In contrast, Bacillus strains which are facultative anaerobes such as Bacillus licheniformis, will be more appropriate for long term co-culturing with Clostridium strains under anaerobic conditions.
Brucella are small (0.5 to 0.7 by 0.6 to 1.5 μm), gram negative, non-motile, non- encapsulated, non-spore forming, rod shaped (coccobacilli) bacteria which are facultative intracellular parasites.
In contrast to other pathogenic mycobacteria, which are facultative intracellular pathogens of macrophages, MU is seen as extracellular clusters of bacilli lying within areas of coagulative necrosis that extend some distance from the site of bacterial colonisation (Forbes et al., 1954).
Second, Bacillus subtilis (ATCC 6633) is another GRAM+ bacteria, which is a facultative pathogen commonly found in the soil [ 29].
In contrast, the only one basidiomycete lacks any of them is Malassezia globosa, which is a facultative parasitic fungus causing dandruff on human skin.
Propionibacterium acnes, which is a facultative anaerobic gram-positive bacterium, is believed to play a critical role in the induction and maintenance of inflammation in acne by activating inflammatory cells, keratinocytes, and sebocytes to induce various inflammatory mediators [ 3, 23].
The remarkably large number of TRGs in the Bathymodiolus SOX symbionts bears striking similarity to the arsenal of toxins encoded by Candidatus Hamiltonella defensa, which is a facultative symbiont of aphids (Oliver et al., 2003, 2005).
In contrast to Nosp, which is a facultative symbiont, NoAz spends its entire life cycle in a perpetual plant interaction and has suffered severe loss of function with a massive number of pseudogenes mainly in the functional categories related to replication, secondary metabolite biosynthesis, and signal transduction [ 8].
The most versatile of the group is S. cerevisiae, which is considered a facultative aerobic fermenter that can ferment under both aerobic and anaerobic conditions and is capable of facultative growth under anaerobic conditions.
