Lactobacillus sanfranciscensis: Difference between revisions

From MicrobeWiki, the student-edited microbiology resource
No edit summary
No edit summary
Line 4: Line 4:
<br>This page was curated by <b>Kay Burrows</b> for Dr. Joan Slonczewski's Microbiology Class, Spring 2018.<br>
<br>This page was curated by <b>Kay Burrows</b> for Dr. Joan Slonczewski's Microbiology Class, Spring 2018.<br>
<br>Lactobacillus sanfranciscensis is a rod-shaped, Gram positive, lactic acid bacteria, closely related to the Lactobacillus casei-Pediococcus group. It is nonsporulating, nonrespiring, acid- and aero-tolerant. Famous for being an important flavor component of sourdough bread, Lb. sanfranciscensis is an obligate, heterofermentative bacteria. Its fastidiousness arises from a symbiotic relationship with Saccharomyces cerevisiae. This yeast, also useful in the making of sourdough, provides L. sanfranciscensis with amino acids and peptides to aid in growth and fermentation. During fermentation, the microbe consumes maltose and glucose to ultimately release acids that create the sour taste in sourdough.<ref>[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3231932/pdf/1475-2859-10-S1-S6.pdf : Vogel RF, Pavlovic M, Ehrmann MA, et al. Genomic analysis reveals Lactobacillus sanfranciscensis as stable element in traditional sourdoughs. Microbial Cell Factories. 2011.]</ref>
<br>Lactobacillus sanfranciscensis is a rod-shaped, Gram positive, lactic acid bacteria, closely related to the Lactobacillus casei-Pediococcus group. It is nonsporulating, nonrespiring, acid- and aero-tolerant. Famous for being an important flavor component of sourdough bread, Lb. sanfranciscensis is an obligate, heterofermentative bacteria. Its fastidiousness arises from a symbiotic relationship with Saccharomyces cerevisiae. This yeast, also useful in the making of sourdough, provides L. sanfranciscensis with amino acids and peptides to aid in growth and fermentation. During fermentation, the microbe consumes maltose and glucose to ultimately release acids that create the sour taste in sourdough.<ref>[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3231932/pdf/1475-2859-10-S1-S6.pdf : Vogel RF, Pavlovic M, Ehrmann MA, et al. Genomic analysis reveals Lactobacillus sanfranciscensis as stable element in traditional sourdoughs. Microbial Cell Factories. 2011.]</ref>
There are over 180 species of Lactobacillus currently documented. Lactobacillus can be found in the human reproductive system as well as the urinary and digestive tracts.  A major contributor to gut flora, Lactobacilli have numerous beneficial roles in the human gastrointestinal tract, including immunomodulation and nutrient breakdown. More than 50 species of Lactobacilli are known as useful non-pathogenic bacteria for the processing of different foods, or for medical application in restoring normal, healthy flora to the skin, vaginal biofilm, and digestive tract. Many species within Lactobacillus have a high hydrogen peroxide tolerance, lending further to their role in inhibiting potential pathogens.
There are over 180 species of Lactobacillus currently documented. Lactobacillus can be found in the human reproductive system as well as the urinary and digestive tracts.  A major contributor to gut flora, Lactobacilli have numerous beneficial roles in the human gastrointestinal tract, including immunomodulation and nutrient breakdown. More than 50 species of Lactobacilli are known as useful non-pathogenic bacteria for the processing of different foods, or for medical application in restoring normal, healthy flora to the skin, vaginal biofilm, and digestive tract. Many species within Lactobacillus have a high hydrogen peroxide tolerance, lending further to their role in inhibiting potential pathogens.
Among this genus, of course, is L. sanfranciscensis, containing a very small genome and a relatively high ratio of rRNA operons, crucial for rapid growth. Unlike the majority of homofermentative lactobacilli, L. sanfranciscensis uses heterofermentative metabolism, processing sugars into either lactic acid or alcohol. This unique processing is what contributes to its role in sourdough formation. Ultimately, we will aim to answer the question: How do we form the ideal sourdough using these microbes?
Among this genus, of course, is L. sanfranciscensis, containing a very small genome and a relatively high ratio of rRNA operons, crucial for rapid growth. Unlike the majority of homofermentative lactobacilli, L. sanfranciscensis uses heterofermentative metabolism, processing sugars into either lactic acid or alcohol. This unique processing is what contributes to its role in sourdough formation. Ultimately, we will aim to answer the question: How do we form the ideal sourdough using these microbes?
<ref>[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3231932/pdf/1475-2859-10-S1-S6.pdf : Vogel RF, Pavlovic M, Ehrmann MA, et al. Genomic analysis reveals Lactobacillus sanfranciscensis as stable element in traditional sourdoughs. Microbial Cell Factories. 2011.]</ref><br>
<br>





Revision as of 18:38, 24 April 2018

This is a curated page. Report corrections to Microbewiki.

Introduction

Scanning electron micrograph of Lactobacillus sanfranciscensis.


This page was curated by Kay Burrows for Dr. Joan Slonczewski's Microbiology Class, Spring 2018.

Lactobacillus sanfranciscensis is a rod-shaped, Gram positive, lactic acid bacteria, closely related to the Lactobacillus casei-Pediococcus group. It is nonsporulating, nonrespiring, acid- and aero-tolerant. Famous for being an important flavor component of sourdough bread, Lb. sanfranciscensis is an obligate, heterofermentative bacteria. Its fastidiousness arises from a symbiotic relationship with Saccharomyces cerevisiae. This yeast, also useful in the making of sourdough, provides L. sanfranciscensis with amino acids and peptides to aid in growth and fermentation. During fermentation, the microbe consumes maltose and glucose to ultimately release acids that create the sour taste in sourdough.[1]

There are over 180 species of Lactobacillus currently documented. Lactobacillus can be found in the human reproductive system as well as the urinary and digestive tracts. A major contributor to gut flora, Lactobacilli have numerous beneficial roles in the human gastrointestinal tract, including immunomodulation and nutrient breakdown. More than 50 species of Lactobacilli are known as useful non-pathogenic bacteria for the processing of different foods, or for medical application in restoring normal, healthy flora to the skin, vaginal biofilm, and digestive tract. Many species within Lactobacillus have a high hydrogen peroxide tolerance, lending further to their role in inhibiting potential pathogens. Among this genus, of course, is L. sanfranciscensis, containing a very small genome and a relatively high ratio of rRNA operons, crucial for rapid growth. Unlike the majority of homofermentative lactobacilli, L. sanfranciscensis uses heterofermentative metabolism, processing sugars into either lactic acid or alcohol. This unique processing is what contributes to its role in sourdough formation. Ultimately, we will aim to answer the question: How do we form the ideal sourdough using these microbes?



Section 1

Include some current research, with at least one figure showing data.

Every point of information REQUIRES CITATION using the citation tool shown above.

Section 2

Include some current research, with at least one figure showing data.

Section 3

Include some current research, with at least one figure showing data.

Section 4

Conclusion

References



Authored for BIOL 238 Microbiology, taught by Joan Slonczewski, 2018, Kenyon College.