Limits...
Ultrastructural study on the morphological changes in indigenous bacteria of mucous layer and chyme throughout the rat intestine.

Mantani Y, Ito E, Nishida M, Yuasa H, Masuda N, Qi WM, Kawano J, Yokoyama T, Hoshi N, Kitagawa H - J. Vet. Med. Sci. (2015)

Bottom Line: The vacuoles were more frequently found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a large majority of bacteria in both the mucous layer and chyme throughout the large intestine.Lysis or detachment of the cell wall in the indigenous bacteria was more frequently found in the large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were distributed almost evenly throughout the intestine.In an experimental control of long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles were also found, but cell-wall degeneration was never observed.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.

ABSTRACT
Indigenous bacteria in the alimentary tract are exposed to various bactericidal peptides and digestive enzymes, but the viability status and morphological changes of indigenous bacteria are unclear. Therefore, the present study aimed to ultrastructurally clarify the degeneration and viability status of indigenous bacteria in the rat intestine. The majority of indigenous bacteria in the ileal mucous layer possessed intact cytoplasm, but the cytoplasm of a few bacteria contained vacuoles. The vacuoles were more frequently found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a large majority of bacteria in both the mucous layer and chyme throughout the large intestine. In the dividing bacteria of the mucous layer and chyme throughout the intestine, the ratio of area occupied by vacuoles was almost always less than 10%. Lysis or detachment of the cell wall in the indigenous bacteria was more frequently found in the large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were distributed almost evenly throughout the intestine. In an experimental control of long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles were also found, but cell-wall degeneration was never observed. From these findings, indigenous bacteria in the mucous layer were ultrastructurally confirmed to be the source of indigenous bacteria in the chyme. Furthermore, the results suggested that indigenous bacteria were more severely degenerated toward the large intestine and were probably degraded in the intestine.

No MeSH data available.


Related in: MedlinePlus

a) The relative frequencies of indigenous bacteria with vacuoles in the mucous layer(light gray column) or chyme (dark gray column) in each intestinal segment. Asterisk,P<0.05. Double asterisks, P<0.01. I, ileum.C, cecum. AC, ascending colon. R, rectum. ND, not determined. b) The number ofindigenous bacteria having each 10% vacuole occupancy in their cytoplasm in the mucouslayer of the ileum (black diamond), cecum (white square) and ascending colon (blacktriangle).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4591154&req=5

fig_002: a) The relative frequencies of indigenous bacteria with vacuoles in the mucous layer(light gray column) or chyme (dark gray column) in each intestinal segment. Asterisk,P<0.05. Double asterisks, P<0.01. I, ileum.C, cecum. AC, ascending colon. R, rectum. ND, not determined. b) The number ofindigenous bacteria having each 10% vacuole occupancy in their cytoplasm in the mucouslayer of the ileum (black diamond), cecum (white square) and ascending colon (blacktriangle).

Mentions: In the ileal mucous layer, the majority of indigenous bacteria possessed intact cytoplasm,which was divided into two parts: cytoplasmic matrices with homogenous high electron densityand nucleoid bodies with low electron density. On the other hand, in the mucous layers ofthe cecum and ascending colon, indigenous bacteria with intact cytoplasm were few, butvacuolated indigenous bacteria were numerously contained. These low-electron-densityvacuoles were variously sized, were not surrounded by cell membrane and were found in almostall bacteria with different morphologies throughout the intestine. The ratio of areaoccupied by vacuoles in the bacterial cytoplasm was less than 10% in the ileal mucous layer,but more than 10% in those of the cecum and ascending colon (Figs. 1a– 1d, 2a, 2bFig. 2.


Ultrastructural study on the morphological changes in indigenous bacteria of mucous layer and chyme throughout the rat intestine.

Mantani Y, Ito E, Nishida M, Yuasa H, Masuda N, Qi WM, Kawano J, Yokoyama T, Hoshi N, Kitagawa H - J. Vet. Med. Sci. (2015)

a) The relative frequencies of indigenous bacteria with vacuoles in the mucous layer(light gray column) or chyme (dark gray column) in each intestinal segment. Asterisk,P<0.05. Double asterisks, P<0.01. I, ileum.C, cecum. AC, ascending colon. R, rectum. ND, not determined. b) The number ofindigenous bacteria having each 10% vacuole occupancy in their cytoplasm in the mucouslayer of the ileum (black diamond), cecum (white square) and ascending colon (blacktriangle).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4591154&req=5

fig_002: a) The relative frequencies of indigenous bacteria with vacuoles in the mucous layer(light gray column) or chyme (dark gray column) in each intestinal segment. Asterisk,P<0.05. Double asterisks, P<0.01. I, ileum.C, cecum. AC, ascending colon. R, rectum. ND, not determined. b) The number ofindigenous bacteria having each 10% vacuole occupancy in their cytoplasm in the mucouslayer of the ileum (black diamond), cecum (white square) and ascending colon (blacktriangle).
Mentions: In the ileal mucous layer, the majority of indigenous bacteria possessed intact cytoplasm,which was divided into two parts: cytoplasmic matrices with homogenous high electron densityand nucleoid bodies with low electron density. On the other hand, in the mucous layers ofthe cecum and ascending colon, indigenous bacteria with intact cytoplasm were few, butvacuolated indigenous bacteria were numerously contained. These low-electron-densityvacuoles were variously sized, were not surrounded by cell membrane and were found in almostall bacteria with different morphologies throughout the intestine. The ratio of areaoccupied by vacuoles in the bacterial cytoplasm was less than 10% in the ileal mucous layer,but more than 10% in those of the cecum and ascending colon (Figs. 1a– 1d, 2a, 2bFig. 2.

Bottom Line: The vacuoles were more frequently found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a large majority of bacteria in both the mucous layer and chyme throughout the large intestine.Lysis or detachment of the cell wall in the indigenous bacteria was more frequently found in the large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were distributed almost evenly throughout the intestine.In an experimental control of long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles were also found, but cell-wall degeneration was never observed.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Histophysiology, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan.

ABSTRACT
Indigenous bacteria in the alimentary tract are exposed to various bactericidal peptides and digestive enzymes, but the viability status and morphological changes of indigenous bacteria are unclear. Therefore, the present study aimed to ultrastructurally clarify the degeneration and viability status of indigenous bacteria in the rat intestine. The majority of indigenous bacteria in the ileal mucous layer possessed intact cytoplasm, but the cytoplasm of a few bacteria contained vacuoles. The vacuoles were more frequently found in bacteria of ileal chyme than in those of ileal mucous layer and were found in a large majority of bacteria in both the mucous layer and chyme throughout the large intestine. In the dividing bacteria of the mucous layer and chyme throughout the intestine, the ratio of area occupied by vacuoles was almost always less than 10%. Lysis or detachment of the cell wall in the indigenous bacteria was more frequently found in the large intestine than in the ileum, whereas bacterial remnants, such as cell walls, were distributed almost evenly throughout the intestine. In an experimental control of long-time-cultured Staphylococcus epidermidis on agar, similar vacuoles were also found, but cell-wall degeneration was never observed. From these findings, indigenous bacteria in the mucous layer were ultrastructurally confirmed to be the source of indigenous bacteria in the chyme. Furthermore, the results suggested that indigenous bacteria were more severely degenerated toward the large intestine and were probably degraded in the intestine.

No MeSH data available.


Related in: MedlinePlus