乳酸菌及びビフィズス菌の消化管定着機構の解明と感染予防への応用

誌名誌名 ミルクサイエンス = Milk science

ISSNISSN 13430289

巻/号巻/号 663

掲載ページ掲載ページ p. 219-226

発行年月発行年月 2017年12月

農林水産省 農林水産技術会議事務局筑波産学連携支援センターTsukuba Business-Academia Cooperation Support Center, Agriculture, Forestry and Fisheries Research CouncilSecretariat

Milk Science Vol. 66, No. 3 2017

一平成29年度日本酪農科学会奨励賞 受賞記念総説

Study of the adherence properties of Lactobacillus and Bifidobacterium species

to intestinal tract and application to the prevention of pathogenic infection

Keita Nishiyama*

(Department of Microbiology, School of Pharmacy, Kitasato University, Minato-ku, Tokyo, 108-8641, Japan)

1. Introduction

The human gastrointestinal (GI) microbiota is

estimated to contain more than 1014 bacterial cells

from 1,000 or more species that form an extremely

complex microbial ecosystem1l. GI micro biota

affect many aspects of host physiology, such as

metabolic phenotype, nutrient absorption and

production, pathogenic infection, and regulation of

the immune system. Consequently, the behavior of

the intestinal microbiota influences host health.

Certain bacteria can be proactively consumed to

directly or indirectly improve the microbiota com-

position, thereby exerting health -maintaining

effects in the host GI tract1,2l. According to the in-

ternational scientific association for probiotics and

prebiotics, a pro biotic is defined as "a live microor-

ganism that, when administered in adequate

amounts, confers a health benefit on the host"3l.

The most commonly applied probiotic bacteria are

Lactobacillus and Bifidobacterium species.

The genus Lactobacillus comprises a large heter-

ogeneous group of low-G + C, gram-positive bacter-ia of the family Lactobacillaceae, class Bacilli.

With over 145 species, the very diverse genus

Lactobacillus is the largest among the lactic acid

bacteria. Lactobacillus species are present through-

out the GI tracts of mammals. Lactobacillus species

are often detected as dominant bacteria from the

duodenum to the terminal ileum in the adult human

* Corresponding Author : Keita Nishiyama Department of Microbiology, School of Pharmacy, Kitasato University, Minato-ku, Tokyo, 108-8641, Japan. (Tel : + 81-3-5719-6256, Fax : + 81-3-3444-4831, E-mail: nishiyamak@pharm.kitasato-u.ac.jp) October 31, 2017 accepted [doi:10.11465/milk.66.219]

gut, and in the female urogenital tract.

The genus Bifidobacterium comprises high-G + C,

gram-positive bacteria of the family Bifidobacteria-

ceae, class Actinobacteria. Bifidobacteria are par-

ticularly abundant among microbial communities

residing in the large intestine of breast-fed infants.

Some bifidobacterial species, such as Bifidobacteri-

um bifidum, Bifidobacterium breve, Bifidobacterium

longum subsp. inf antis, and Bifidobacterium longum

subsp. longum, are specific to the human GI tract

and are among the dominant bacterial members of

the intestinal microbiota of breast-fed infants.

The intestinal mucosal surface component is the

first point of contact for intestinal microbes, includ-

ing Lactobacillus and Bifidobacterium4,5l. Adhesion

to the mucosal surface has been considered to

prolong bacterial persistence in the GI tract

environment and their beneficial effects to the host.

The adhesion capacity of Lactobacillus and

Bifidobacterium might depend on bacterial cell-sur-

face components4-8l. In the light of our research

focuses on bacteria-host interaction processes, we

have been studying bacterial cell-surface adhesion

factors. In previous studies, we have identified and

characterized the interactions of adhesion factors

with receptor molecules. Elongation factor Tu

(EF-Tu) from Lactobacillus reuteri binds to sulfat-

ed carbohydrate moieties of glycocalyx and

mucins9l, mucus-binding factor from Lactobacillus

rhamnosus binds to certain extracellular matrix

(ECM) proteins and mucins10l, aggregation prom-

pting-factor (APF) from Lactobacillus gasseri binds

to fibronectin11l, SpaC pili from Lactobacillus rham-

nosus bind to [J-galactoside at the non-reducing

terminus of glycolipids12l, and sialidase from B.

bifidum binds to colonic mucin13l. Moreover, the

competition with pathogens for the same receptor

220

site (s) on the host mucosal surface has been consi-

dered one of the strategies for the clearance of

infectious bacteria by probiotics14l. Figure 1 sum-

marizes the current knowledge on the mechanisms

of competitive exclusion in pathogen infection by

probiotic bacteria. One of our research aims is to

apply the knowledge on the characterized adhesion

factors to the prevention of pathogen infections.

In the first part of this review, we will summarize

the molecular mechanisms underlying the inhibito-

ry effects of adhesive Lactobacillus strains on Cam-

pylobacter and Helicobacter infection mediated

through adhesion site competition. In the second

part, we will focus on the extracellular glycoside

hydrolase-mediated colonization process unique to

B. bifidum that we recently discovered.

2. Adhesion of Lactobacil/us strains to the

intestinal tract and application to patho-

genic infection control

(1) Prevention of Helicobacter infection

Helicobacter pylori is a spiral-shaped, gram-nega-

tive bacterium that colonizes the gastric and duo-

den um mucosa in more than 50 % of the world

population. H pylori was first isolated by Marshall

and Warren, who identified this organism as a

major cause of peptic ulcers and gastric adenocar-

cinoma 15l. Triple therapy including a proton pump

inhibitor, clarithromycin, and amoxicillin is one of

the most commonly used treatments for H pylori.

The efficacy of this treatment is strongly affected

by the occurrence of clarithromycin resistance; in

Japan, the success rate is only 70%16l.

Adhesion of H pylori to the mucosal surface con-

stitutes a key step in successful colonization of the

host GI tract and is characterized by the interaction

with several receptor molecules, such as blood

group ABO antigens, sialylated Lewis antigens of

mucin, and sulfated glycoconjugates17l. Therefore,

we thought that adhesion of Lactobacillus strains to

these molecules can competitively inhibit the adhe-

sion of H pylori.

Mukai and colleagues previously reported that

Lactobacillus reuteri JCM1081 adheres to asialo-

GMl and sulfatide18l. These authors applied cell-

surface extracts from L. reuteri JCM1081 to an

agarose gel-immobilized galactose 3-sulfate probe

第66巻

corresponding to the carbohydrate moiety of sulfa-

tide, and thus identified a ~47-kDa protein as a

candidate sulfatide-binding protein18l. Based on its

N-terminal amino acid sequence, the protein was

identified as EF-Tu, encoded by the tuf gene9l. To

characterize EF-Tu binding properties, surface

plasmon resonance (SPR) analysis was performed

to determine whether EF-Tu interacts with sulfat-

ed glycoconjugates. SPR analysis demonstrated

that recombinant EF-Tu binds to sulfatide and

sulfated mucin, but not to neutral or sialylated

glycolipids, indicating that a sulfated carbohydrate

residue is responsible for EF-Tu binding.

Moreover, adhesion or L. reuteri JCM1081 to

mucin was blocked in an anti-EF-Tu antibody

concentration-dependent matter, indicating that

EF-Tu is involved in L. reuteri adhesion to mucin.

Therefore, the binding of EF-Tu to sulfated carbo-

hydrate moieties of glycoconjugates and mucin

might promote Lactobacillus adhesion to the

mucosal surface9l (Fig. 1).

We evaluated EF-Tu-mediated H pylori inhibi-

tion using recombinant EF-Tu protein in an in vitro

assay. Because EF-Tu is a housekeeping protein,

tuf mutant strains are lethal. The addition of

recombinant EF-Tu inhibited the adhesion of H

pylori American Type Culture Collection (ATCC)

strains and clinical isolates to porcine gastric mucin

ma concentration-dependent manner19l (Fig. 2A).

This competition effect was significantly lower on

sulfatase-treated porcine gastric mucin, which sug-

gested that the EF-Tu inhibitory effect is mediated

by sulfated carbohydrates (Fig. 2B). We further

examined whether administration of EF-Tu-

expressing Lactobacillus strains is effective for

suppressing H pylori Sydney strain 1 (SSl) coloni-

zation in a C57BL/6J mouse model2°l. C57BL/6J

mice were intragastrically administered Lactobacil-

lus strains once daily, starting two days before

intragastric inoculation with H pylori SSl and

continuing for 15 days after inoculation. Among

the five Lactobacillus strains examined (L. gasseri

KZ1201, L. gasseri SBT2055, L. reuteri JCM1081,

L. rhamnosus ATCC 53103, and Lactobacillus joh-

nsonii KZ1002), four strains exhibited significant

preventive efficacy against H pylori SSl at day 15

of infection. Interestingly, the non-inhibitory strain

L. johnsonii KZ1002 showed lower EF-Tu cell-sur-

第 3号 221

Fig. 1 Schematic representation of the processes of bacterial competitive exclusion in pathogen infection Left, Scheme summarizing inhibition of He/icobacter and Campylobacter infection mediated through competition for the same adhesion sites by adhesive probiotic strains. Right, Scheme summarizing identified bacterial adhesion factors and their target ligand molecules in the host GI tract.

(A)

■ Non-treated □Recombinant EF-Tu

◇

e

べ‘’究ん

汐

ら心令

ら◇゜＆

ら

らe

9

c ｀

e ◇

8

7

6

5

0

0

0

0

1

1

1

1

(―-。さnも）upn E :ip1se6 aupJod

.I

B 0¥ 9699Z: :::J::H¥I /JO/A Q'H JO UOIS84P¥I

,1し

ヘや）

s

凸

n

．

へへ

a

r

t

心

s

ぃ

．

n

心もト

YJop ゚

゜

も命

令

H

8

7

6

5

や

0

0

0

0

0

1

1

1

1

0

ペや

(uaMJn::18) upnw ::>!J¥se6 aupJod

0ごJD/Ad•

H io uo1sa4p¥f

＊

I I n.s. n.s. I i I

Fig. 2

n.s.

EF-Tu from L. reuteri JCM 1081 inhibits the adhesion of H. pylori strains to mucin (A) Inhibition of the adhesion of H. pylori strains to porcine gastric mucin by recombinant EF-Tu protein. (B) Effects of treatment with sulfatase on the inhibition of H. pylori by recombinant EF-Tu protein. All data are presented as the mean CFU/well土SD.*p<0.05. "n.s.," not significant. Reprinted from Nishiyama et al. (2017) 19) with permission of the Japanese Dairy Science Association.

face expression than the four effective strains19l.

Based on these findings, we propose that EF-Tu-

mediated adhesion of Lactobacillus to sulfated car-

bohydrates might be an important process under-

lying their H pylori inhibitory effect.

(2) Prevention of Campylobacter infection

Campylobacter spp. have been recognized as the

leading cause of enteric bacterial infections affect-

ing the human GI tract. Campylobacter jejuni is the

most frequently isolated from infected humans21l.

C. jejuni is a typical zoonotic pathogen as it can

colonize poultry and domestic animals, and is main-

ly transmitted by the handling and consumption of

contaminated poultry meat21l. Thus, reducing C.

jejuni colonization in the intestinal tracts of poultry

has been proposed as an approach to decreasing

the disease burden in humans.

L. gasseri SBT2055 is considered as a candidate

probiotic strain owing to is ability to establish in

the human GI tract22l. In a chick colonization

assay, oral doses of L. gasseri SBT2055 were

administered to chicks daily for 14 days after

inoculation with C. jejuni 81-176. At 14 days post

inoculation, chicks treated with L. gasseri

SBT2055 had a significantly lower C. jejuni coloni-

zation level in the cecum than control chicks. L.

gasseri SBT2055 also lowered C. jejuni adhesion to

and internalization by human epithelial cells,

indicating that it effectively and competitively

excludes C. jejuni23l. Moreover, the co-aggregation

phenotype and/ or adhesion mediated by cell

surface components might be involved in the inhi-

bition of C. jejuni23).

222

APF is cell surface proteins that have been

characterized for several Lactobacillus species24l.

These proteins have been considered to be related

to bacterial adhesion and aggregation. We focused

on the functional roles of L. gasseri SBT2055 cell-

surface APFs (APFl and APF2) in the inhibitory

effects of L. gasseri SBT2055 on C. jejuni infection.

An L. gasseri SBT2055 apfl knockout (Llapfl)

strain showed abolished self-aggregation as com-

pared to the wild-type and apf2 knockout (Llapf2)

strains. Adhesion of the Llapfl strain to epithelial

cells was significantly lower than that of the wild-

type and Llapf2 strains. Thus, APFl is involved in

the L. gasseri SBT2055 adhesion and aggregation

phenotypes11l. C. jejuni adhesion to and invasion of

human epithelial cells were significantly inhibited

by the L. gasseri SBT2055 wild-type and Llapf2

strains, but not the Llapfl strain. Chicks treated

with L. gasseri SBT2055 wild-type and apf2 strains

showed significant inhibition of cecum colonization

by C. jejuni when compared to the Llapfl strain-

treated group (Fig. 3A). Interestingly, co-aggre-

gation with C. jejuni 81-176 was similar between

Llapfl and Llapf2 (Fig. 3B). These results suggest

that competitive adhesion rather than co-aggrega-

tion is the main process underlying the inhibitory

effects of APFl on C. jejuni inhibition叫

ECM proteins, such as fibronectin, laminin, and

collagen, are some of the major receptors support-

ing bacterial adhesion to epithelial cells25l. In an

SPR analysis to evaluate the binding of recom-

binant APFs to these ECM proteins, interestingly,

recombinant APFl was shown to have high affinity

to fibronectin, while APF2 did not bind to this

protein11l (Fig. 1). Fibronectin is one of the recep-

tor molecules mediating C. jejuni colonization of

the GI tract, as evidenced by previous studies

showing that adhesion of C. jejuni to :fibronectin is

required for invasion of human epithelial cells as

well as for GI tract colonization in chicken26l.

Therefore, this report supports our notion that

inhibition of C. jejuni by L. gasseri SBT2055 is

mediated through competition of APFl with C.

jejuni ligands for adhesion sites such as fibronectin

on the intestinal epithelial cell surface11l.

We demonstrated that cell surface-associated

APFl is important in L. gasseri SBT2055 adhesion

and aggregation, and that the adhesion activity of

(A) .-. ＊＊

3 ..

〗：二．i iEI~ 森 ❖~C 0 104 ーニ丹 103・1s 、0ら

｀゚゚'" ¥'l-

8 o<:'#o ~~0 。~0\l

I> I> ~

L. gasseri strains

Fig. 3

゜

ー↓一

300250200150100500

旧

s11unaoueuosa~

500

第66巻

2↓

町

1000 1500 2000

Time (s)

APF from L gasseri SBT2055 facilitates competi-tive exclusion of C. jejuni (A) APF1-producing L. gasseri strains inhibit C. jejuni colonization and persistence in chicks. **p く0.01versus C. jejuni alone. Lines indicate median CFU values for each group. (B) lnterac-tion of L. gasseri strains and C. jejuni as assessed by SPR analysis. Arrows indicate sample injec-tion points. Reprinted from Nishiyama et al. (2015) 11l with permission of John Wiley & Sons Ltd.

L. gasseri SBT2055 is important for the reduction

in C. jejuni infection and colonization11l. This find-

ing confirms the idea of competitive exclusion of C.

jejuni mediated by cell-surface component of L.

gasseri SBT2055 playing a key role in the preven-

tion of pathogen infection.

3. Extracellular sialidase-mediated adhesion

of B. bifidum

Bifidobacteria are thought to employ a variety

of microbe -host interaction mechanisms that

facilitate GI tract colonization5,7,8l; however, the

underlying molecular mechanisms are not fully

understood. We have previously demonstrated that

the adhesion of 22 Bifidobacterium strains to por-

cine colonic mucins varied markedly, with some

strains showing specific interactions with mucin

carbohydrate moieties27l. We hypothesized that

Bifidobacterium strains carrying lectin-like adhe-

sion molecule (s) on the cell surface could promote

the bacteria-mucosal surface interaction, thus

facilitating bifidobacterial establishment in the GI

tract. In this section, I describe a novel extracellu-

lar sialidase-mediated colonization process that is

unique to B. bifidum.

Bifidobacterium species reside in the large

intestine, where there is a low abundance of

sugars; their survival and growth therefore

第 3号 223

requires a variety of extracellular and cytoplasmic

glycosyl hydrolases that hydrolyze indigestible

oligosaccharides28l. Sialic acids (Neu5Ac) are

frequently found at the non-reducing termini of

sugar chains on various eukaryotic glycocon-

jugates as well as at the terminal position of human

milk oligosaccharide (HMO). As sialic acid pro-

vides a negative charge, sialic acid-containing

carbohydrates are resistant to several bacterial

glycosidases. Therefore, removal of sialic acid

from HMOs and intestinal glycoconjugates

exposes the glycan moiety and is considered to

hasten their catabolism.

B. bifidum extracellular sialidase (SiaBb2, Fig.

4A) might play a role in bifidobacterial catabolism

of sialylated carbohydrates. However, the func-

tional role of sialidase in Bifidobacterium growth

remains unknown. Using the B. bifidum ATCC

15696 siaBb2 knock out (L1siabb2) strain, we

demonstrated that SiaBb2 promotes the removal of

sialic acid from sialyl-HMO and -mucin glycans to

yield utilizable oligosaccharides. Interestingly,

L1siabb2 showed a significantly lower ability to

adhere to epithelial cells and porcine colonic mucin

than the wild-type strain, while adhesion was

restored to the wild-type level in a siabb2 com-

plementation strain. This finding indicated that

SiaBb2 plays a role in the mucin-adhesive ability of

B. bifidum A TCC 1569613l.

To futher characterize SiaBb2-mediated B. bifi-

dum adhesion further, we examined the binding of

recombinant SiaBb2 peptides to porcine colonic

mucins. Recombinant conserved Sialidase domain

peptides (see Fig. 4A) bound to mucin with simi-

lar efficacies. Interestingly, the sialidase domain is

responsible for the interaction, as the binding of

SiaBb2 was less effective upon desialylation of

mucin by mild acid hydrolysis. These results

suggest that SiaBb2 can recognize sialylated carbo-

hydrates of porcine colonic mucin as well as other

carbohydrates. A glycoarray assay revealed that

sialidase domain peptides bind to the幽 6-linked

sialic acid on sialyloligosaccharide and blood type

A antigen at the non-reducing termini of sugar

chains (Fig. 4B). This finding indicates that the

sialidase domain is responsible for the interaction,

and that SiaBb2 recognizes two different carbohy-

drate structures via lectin-like interaction13l (Fig.

(A) 1 36

SiaBb2 N-0

Signal sequence

Fig. 4

187 553

Sialidase domain

572 634

a-galactase domain

402000806040200

1

1

1

ap,idad U!B E op asep11e1s

＇ー、B

」

o6u1pu1q a > !lBl8~

＇ー，

↓

•

(8N)0

g)8

(9N)<

(sz

ごUNl

（芯ごZ1

(cz)OW3 S9

(g) O¥fN7S£

(LN) 7S9

(ON) 7S£

(6~)

oe7

(a~)

xa1s

E) ea1s

(9~)

xa7

(9L)e81

(＜

L) daHO\f/SN•O

(CL) daHSN•O (a) d

aHs9aa

(LL) daHszaa

(OL) U!JBdBH

(6).L

(8)U

切

(

L

)

1'¥IN

(g)£¥I

(S)£¥IN

(r)42N

(

C

)

兒

(

N

)

兒Z

(

L

)

61'¥1

Extracellular SiaBb2 from B. bifidum A TCC 1 5696 enhances its binding to sialyloligosaccha-rides and blood type A antigen. (A) Schematic representation of the primary structure of SiaBb2. Amino acid numbering starts at the presumed initiation codon. (B) Inter-actions of sialidase domain peptide with 28 type-s of sugar chains based on glycoarray signals Strong sialidase domain peptide fluorescence signals corresponding to carbohydrate chains of Siaa2,6 linkage at the non-reducing terminus (gray arrows) and blood type A antigen (black arrow). Reprinted from Nishiyama et al. (2017) lJ).

1).

Together, these findings suggest that extracellu-

lar sialidase from B. bifidum acts as a bifunctional

extracellular glycosidase enhancing Bifidobac-

terium-mucosal surface interactions and supporting

the assimilation of HMOs and intestinal glycocon-

jugates13l. Our breakthrough discovery of the

bifunctional role of extracellular glycoside hydro-

lase will accelerate our understanding of the coloni-

zation mechanisms of Bifidobacterium on the

mucosal surface and help to clarify its survival

strategies.

4. Conclusion

Adhesion to the mucosal surface is a prime

strategy for the colonization and persistence of

non-motile organisms (e.g., Lactobacillus and

Bifidobacterium) in the GI tract and might provide

a competitive advantage in this ecosystem. In this

224

review, we described recently identified and

characterized adhesion factors of Lactobacillus and

Bifidobacterium species and presented a strategy

for preventing Helicobacter and Campy!obacter

infections by applying Lactobacillus adhesion

factors. Probiotic bacteria have been shown to

possess the capacity to competitively inhibit patho-

gen colonization and infection. The competitive

inhibition activity has been considered to occur

through the action of several key mechanisms,

including competition for attachment sites, co-

aggregation with the pathogen, host immune

modulation, and production of antimicrobial com-

pounds or lactic acid14l. Studies indicate that the

effectiveness of the inhibitory effects is mediated

through competition with pathogen ligands for the

same adhesion sites, and provide significant

insights into the mechanisms underlying competi-

tive adhesion of intestinal pathogenic bacteria by

probiotics. Recent studies have revealed the

Bifidobacterium adhesion mechanism, and the

application of these strains is an important direc-

tion for further research. Deepening our under-

standing of the interactions between probiotic bac-

teria and the mucosal surface is anticipated to

reveal important information, including latent

capabilities of probiotics, as well as more specific

applications of these bacteria.

Acknowledgement

I am deeply honored to have received an

Encouragement Award from the Japanese Dairy

Science Association. I extend my heartfelt thanks

to the President of the Association, Dr. Tadao

Saito, as well as to the professors and scientists

who served on the panel of judges. All research

described in this review was carried out in collabo-

ration with Drs. Takao Mukai and Yuji Yamamoto

(Kitasato University). During this research, I

received support from many collaborators, col-

leagues, and students, to whom I am sincerely

grateful.

Funding

The research described herein was supported by

JSPS KAKENHI Grant Numbers 24580397,

15K07709, and 15H06581 and by a Kitasato

University Research Grant for Young Researchers.

第66巻

Part of this work was funded by Megmilk Snow

Brand Co., Ltd.

References

1) Fujimura, K. E., Slusher, N. A., Cabana, M. D., and

Lynch, S. V.: Role of the gut microbiota in defining

human health. Expert Rev. Anti. Infect. Ther., 8, 435-

454 (2010)

2) Guinane, C. M., and Cotter, P. D.: Role of the gut

microbiota in health and chronic gastrointestinal

disease: understanding a hidden metabolic organ.

Therap. Adv. Gastroenterol., 6, 295-308 (2013)

3) Hill, C., Guarner, F., Reid, G., Gibson, G. R.,

Merenstein, D. J., Pot, B., Morelii, L., Canani, R. B.,

Flint, H. J., Salminen, S., Calder, P. C. and Sanders,

M. E.: Expert consensus document. The International

Scientific Association for Probiotics and Prebiotics

consensus statement on the scope and appropriate use

of the term pro biotic. Nat. Rev. Gastroenterol. Hepatol.,

11, 506-514 (2014)

4) Nishiyama, K., Sugiyama, M., and Mukai, T.:

Adhesion properties of Lactic Acid Bacteria on intesti-

nal mucin. Microorganisms, 4, 34 (2016)

5) 向井孝夫・西山啓太：プロバイオティクスに関する

最近の研究動向：乳酸菌やビフィズス菌のムチンと

の相互作用．乳業技術， 65,23-40 (2015)

6) 西山啓太・ 向井孝夫：乳酸菌とムチンの相互作用：

糖鎖を介した乳酸菌の腸粘膜への付着機構．応用糖

質科学， 5,38-43 (2015)

7) 西山啓太・向井孝夫：乳酸菌の腸粘膜への定着機

構．化学と生物， 54,471-477 (2016)

8) 西山啓太・向井孝夫： Lactobacillus属やBifidobacteri-

um属の宿主腸粘膜への付着性に関わるアドヘシンと

その分子機構． 日本乳酸菌学会誌， 27,176-186

(2016)

9) Nishiyama, K., Ochiai, A., Tsubokawa, D., Ishihara,

K., Yamamoto, Y. and Mukai, T.: Identification and

characterization of sulfated carbohydrate-binding pro-

tein from Lactobacillus reuteri. PLoS One, 8, e83703

(2013)

10) Nishiyama, K., Nakamata, K., Ueno, S., Terao, A.,

Aryantini, N. P. D., Sujaya, I. N., Fukuda, K.,

Urashima, T., Yamamoto, Y,. and Mukai, T.:

Adhesion properties of Lactobacillus rhamnosus

mucus-binding factor to mucin and extracellular

matrix proteins. Biosci. Biotechnol. Biochem., 78, 271-

279 (2014)

第 3号

11) Nishiyama, K., Nakazato, A., Ueno, S., Seto. Y.,

Kakuda, T., Takai, S., Yamamoto, Y. and Mukai, T.:

Cell surface-associated aggregation-promoting factor

from Lactobacillus gasseri SBT2055 facilitates host

colonization and competitive exclusion of Campylobac-

ter jejuni. Mot. Microbiol., 98, 712-726 (2015)

12) Nishiyama, K., Ueno, S., Sugiyama, M., Yamamoto,

Y., and Mukai, T.: Lactobacillus rhamnosus GG SpaC

pilin subunit binds to the carbohydrate moieties of

intestinal glycoconjugates. Anim. Sci. J, 87, 809-815

(2016)

13) Nishiyama, K., Yamamoto, Y., Sugiyama, M.,

Takaki, T., Urashima, T., Fukiya, S., Yokota, A.,

Okada, N., and Mukai, T.: Bifidobacterium b祈dum

extracellular sialidase enhances adhesion to the

mucosa! surface and supports carbohydrate assimila-

tion. MBio, 8, e00928-17 (2017)

14) Callaway, T. R., Edrington, T. S., Anderson, R. C.,

Harvey, R. B., Genovese, K. J., Kennedy, C. N.,

Venn, D. W., and Nisbet, D. J.: Probiotics, prebiotics

and competitive exclusion for prophylaxis against

bacterial disease. Anim. Health Res. Rev., 9, 217-225

(2008)

15) Marshall, B. J., and Warren, J. R.: Unidentified

curved bacilli in the stomach of patients with gastritis

and peptic ulceration. Lancet, 323, 1311-1315 (1984)

16) 高橋信一・田中昭文• 徳永健吾： H. pylori除茜治療

の最近の話題．日本消化器病学会雑誌， 107,1273-

1282 (2010)

17) Kusters, J. G., van Vliet, A.H. M., and Kuipers, E. J.:

Pathogenesis of Helicobacter pylori infection. Clin.

Microbiol. Rev., 19, 449-490 (2006)

18) Mukai, T., Asasaka, T., Sato, E., Mori, K.,

Matsumoto, M. and Ohori, H.: Inhibition of binding of

Helicobacter pylori to the glycolipid receptors by

probiotic Lactobacillus reuteri. FEMS Immunol. Med.

Microbiol., 32, 105-110 (2002)

19) Nishiyama, K., Kagamitani, T., Yamamoto, Y.,

Okada, N., and Mukai, T.: The elongation factor Tu

from Lactobacillus reuteri inhibits the adhesion of

Helicobacter pyloガtoporcine gastric mucin. Milk Sci.,

66, 17-26 (2017)

20) Matsui, H., Takahashi, T., Overby, A., Murayama, S.

Y., Yoshida, H., Yamamoto, Y., Nishiyama, K., Seto,

225

Y., Takahashi, T., Mukai, T. and Nakamura, M.:

Mouse models for assessing the protective efficacy of

Lactobacillus gasseri SBT2055 against Helicobacter suis

infection associated with the development of gastric

mucosa-associated lymphoid tissue lymphoma.

Helicobacter, 20, 291-298 (2015)

21) Young, K. T., Davis, L. M., and Dirita, V. ].: Cam-

pylobacter jejuni: molecular biology and pathogenesis.

Nat. Rev. Microbiol., 5, 665-679 (2007)

22) Fujiwara, S., Seto, Y., Kimura, A., and Hashiba, H.:

Establishment of orally-administered Lactobacillus

gasseri SBT2055SR in the gastrointestinal tract of

humans and its influence on intestinal microflora and

metabolism. J Appl. Microbiol., 90, 343-352 (2001)

23) Nishiyama, K., Seto, Y., Yoshioka, K., Kakuda, T.,

Takai, S., Yamamoto, Y. and Mukai, T.: Lactobacillus

gasseri SBT2055 reduces infection by and colonization

of Campylobacter jejuni. PLoS One, 9, el08827 (2014)

24) Jankovic, I., Ventura, M., Meylan, V., Rouvet, M.,

Elli, M., and Zink, R.: Contribution of aggregation-

promoting factor to maintenance of cell shape in Lac-

tobacillus gasseri 4B2. J Bacteriol., 185, 3288-3296

(2003)

25) Chagnot, C., Listrat, A., Astruc, T., and Desvaux, M.:

Bacterial adhesion to animal tissues: protein deter-

minants for recognition of extracellular matrix compo-

nents. Cell. Microbiol., 14, 1687-1696 (2012)

26) Boehm, M., Krause-Gruszczynska, M., Rohde, M.,

Tegtmeyer, N., Takahashi, S., Oyarzabal, 0. A., and

Backert, S.: Major host factors involved in epithelial

cell invasion of Campylobacter jejuni: role of fibronec-

tin, integrin betal, FAK, Tiam-1, and DOCK180 in

activating Rho GTPase Rael. Front. Cell. Infect.

Microbiol., 1, 17 (2011)

27) Nishiyama, K., Kawanabe, A., Miyauchi, H., Abe, F.,

Tsubokawa, D., Ishihara, K., Yamamoto, Y. and

Mukai, T.: Evaluation of bifidobacterial adhesion to

acidic sugar chains of porcine colonic mucins. Biosci.

Biotechnol. Biochem., 78, 1444-1451 (2014)

28) Sela, D. A., and Mills, D. A.: Nursing our microbiota:

molecular linkages between bifidobacteria and milk

oligosaccharides. Trends Microbiol., 1 8, 298-307

(2010)

226 第66巻

乳酸菌及びビフィズス菌の消化管定着機構の解明と感染予防への応用

西 山 啓 太

（北里大学薬学部微生物学教室，東京都港区白金 5-9-1 108-8641)

LactobacillusやBifidobacteriumは哺乳類の消化管に広く生息する共生細菌である。これらの細菌にとって宿主腸粘

膜に対する付着性を有することは腸内環境での定着や生存を有利にすると考えられている。これまで筆者は，細菌と宿

主腸粘膜の相互作用に着目し， LactobacillusやBifidobacteriumにおいて複数の付着因子を同定し特徴付けてきた。さ

らに見出された付着特性を利用し，病原細菌との付着部位の競合を利用した感染予防の有用性を証明してきた。本総説

では， Lactobacillusによる CampylobacterとHelicobacterの感染予防に関する取り組みとそのメカニズムについて論じ

るとともに，最近筆者らが見出したBifidobacteriumの糖質分解酵素を介した付着機構について紹介する。