This video, we're going to begin our lesson on fimbriae and hammy. Fimbriae are actually filaments of a pilon protein that are shorter than pili themselves, and they extend from the cell surface of many bacteria. Now the functions of these fimbriae are to adhere cells to one another or to another surface. They are really involved in the formation of biofilms, those communities of microbes that live together within an extracellular polymeric substance. If we take a look at this image down below, you can see that fimbriae adhere to each other connecting cells in a biofilm. Notice that we're showing you a biofilm over here, this community of microbes encased in this extracellular polymeric substance or this EPS structure that you see here. All of these microbes that you see here are living within this biofilm. Zooming into these bacterial cells right here, notice that the bacterial cells have these little structures that are projecting off their surface. These tiny structures that are projecting off of the cell surface are the fimbriae. Once again, these fimbriae function in helping these cells to adhere to each other. You can see that they are going to interact with each other, adhering to each other. But also it allows the cells to adhere to other surfaces as well. They are going to be very important in the formation of biofilms. This here concludes our introduction to fimbriae. Later in our next video, we'll introduce Hammy. So I'll see you all there.
Fimbriae & Hami - Online Tutor, Practice Problems & Exam Prep
Fimbriae & Hami
Video transcript
The presence of fimbriae on a bacterial cell is most likely to have a critical role in
Hami
Video transcript
In this video, we're going to introduce hami. And so hami are short filamentous proteins that are only found on the surface of archaeal cells. And so these hami are specific to archaea and are not really found on bacteria or eukarya. And the hami, they serve as hook-like appendages that act like grapples to allow them to attach to each other and to allow them to attach to other bacterial cells. And so archaeal cells that have hami, they can be found within biofilm communities. And, biofilm communities that have bacterial cells since they can attach to bacterial cells. And so in this example down below, we're showing you how archaeal cells can produce long filamentous cell surface proteins called hami, and how those hami can be found on archaea within biofilms. And so once again over here on the right-hand side, we're showing you a biofilm. And zooming into a region of the biofilm, notice that there are archaea here. And these archaea, on their cell surface, they have these structures that are projecting off, and these structures are representing the hami. And the hami, once again, are going to be the short filamentous proteins that extend only off of the surface of archaeal cells, and they act like hook-like appendages, similar to grapples that allow them to hang on to each other and attach to each other and other bacterial cells as well. And so they're important in the formation of biofilms. And so this here concludes our brief lesson on Hami, and we'll be able to get some practice applying these concepts as we move forward. So I'll see you all in our next video.
Which of the following structure is found only in archaea?