Giant Colony Morphologies
When I undertook this project I never imagined the microbiology involved and the hours I would spend in the lab just to get this project off the ground. Three months in the lab culturing organisms so far and I have found that just working with Brettanomyces spp. on various media agars can prove difficult. Each plate takes careful examination to ensure pure cultures are kept and maintained. Overtime this becomes easier and I have started to memorize traits each strain possess on the different media agars. The majority of the past few months have involved working with the Brettanomyces species cultured from Avery’s 15th Anniversary ale and cultures from White Labs yeast company. I have been culturing the Brettanomyces strains onto various medias listed previously and observed the morphologies and growth habits of each strain. The following is photos from the three White Labs Brettanomyces strains and their unique morphologies on various media agars. Along with culturing the different strains on various medias, careful observation under the microscope helps to observe strains general cell morphology but in no way gives a good indication to whether a pure culture is being observed due to the many growth phases and various cell shapes observed by a single culture at one time. I will try to post photos later and detail cell morphology under a microscope but that is too detailed to include in this post. For now here are some photos of the Brettanomyces spp. cultured on the various agar plates as this may be useful for any one trying to culture this incredibly fickle organism. The most difficult part of observing Brettanomyces is that little is written about the behavior and life cycle, if much is even known at all. I have discovered that even when a single colony is taken and streaked onto the agar plates not every resulting colony will grow exactly uniform or have exactly the same color or size. This could be due to a stage of the life cycle when streaked from a single colony or another phenomena, but it seems to be observed in nearly every strain.
B. claussenii (WLP645) grown on WLN at 4 days since streaking
This species breaks the rules and does not
metabolize the Bromocresol Green
indicator as the literature states
New discovery, look how green the colonies remain