Review article Corynebacterium pseudotuberculosis


Download 357.03 Kb.
Pdf ko'rish
bet1/4
Sana05.10.2017
Hajmi357.03 Kb.
#17169
  1   2   3   4

201

Vet. Res. 37 (2006) 201–218

© INRA, EDP Sciences, 2006

DOI: 10.1051/vetres:2005056



Review article

Corynebacterium pseudotuberculosis: microbiology, 

biochemical properties, pathogenesis and molecular 

studies of virulence

Fernanda Alves D

ORELLAa

, Luis Gustavo Carvalho P



ACHECOa

Sergio Costa O



LIVEIRAb

, Anderson M

IYOSHIa

, Vasco A



ZEVEDOa

*

a



 Laboratório de Genética Celular e Molecular, Departamento de Biologia Geral, Instituto de Ciências 

Biológicas, Universidade Federal de Minas Gerais, CP 486, CEP 31270-901, Belo Horizonte, MG, Brazil

Laboratório de Imunologia de Doenças Infecciosas, Departamento de Bioquímica e Imunologia, 



Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, CP 486, CEP 31270-901, 

Belo Horizonte, MG, Brazil

(Received 2 February 2005; accepted 4 November 2005)

Abstract – Corynebacterium pseudotuberculosis is the etiological agent of caseous lymphadenitis

(CLA), a common disease in small ruminant populations throughout the world. Once established,

this disease is difficult to eradicate because drug therapy is not effective and because the clinical

detection of infected animals is of limited efficiency. We reviewed the microbiological, biochemical

and taxonomic features of C. pseudotuberculosis, general aspects of infection, the main virulence

determinants and currently available commercial vaccines. We also examined the current molecular

strategies for the study of virulence in C. pseudotuberculosis, including the latest research on the

identification of novel virulence factors and genes, which will help us to better understand the

biology of this microorganism. This knowledge may also contribute to the development of

improved CLA vaccines, including subunit and DNA-based types, as well as to improve the

diagnosis, treatment and control of this disease. 

Corynebacterium pseudotuberculosis / caseous lymphadenitis / pathogenesis / virulence /

vaccine

Table of contents

1. Introduction ..................................................................................................................................... 202

2. Microbiological, biochemical and taxonomic features of C. pseudotuberculosis ........................... 202

2.1. Microbiological aspects .......................................................................................................... 202

2.2. Biochemical properties............................................................................................................ 203

2.3. Antimicrobial susceptibility .................................................................................................... 203

2.4. Taxonomy ............................................................................................................................... 206

3. General aspects of C. pseudotuberculosis infection ........................................................................ 207

3.1. Transmission ........................................................................................................................... 207

3.2. Human cases............................................................................................................................ 207

3.3. Caseous lymphadenitis............................................................................................................ 207

* Corresponding author: vasco@icb.ufmg.br

Article published by EDP Sciences and available at 

http://www.edpsciences.org/vetres

or 

http://dx.doi.org/10.1051/vetres:2005056



202

F.A. Dorella et al.

3.4. Epidemiology of CLA .............................................................................................................208

3.5. Diagnosis and control of CLA .................................................................................................208

4. From proteins to DNA: Commercial and experimental vaccines ....................................................208

4.1. Commercial vaccines ...............................................................................................................208

4.2. Experimental vaccines .............................................................................................................210

5. Determinants of virulence  ...............................................................................................................210

5.1. Phospholipase D ......................................................................................................................210

5.2.  Toxic cell-wall lipids ...............................................................................................................211

5.3. New candidates ........................................................................................................................211

6. Molecular strategies for the study of virulence in C. pseudotuberculosis .......................................211

6.1.  Identification of immunodominant peptides............................................................................211

6.2.  Generation of mutants..............................................................................................................212

7. Future directions ...............................................................................................................................212

1. INTRODUCTION 

The genus Corynebacterium belongs to

a suprageneric group of actinomycetes that

also includes the genera Mycobacterium,



Nocardia and Rhodococcus [46, 87, 100, 102].

These gram-positive bacteria (Corynebac-



terium,  Mycobacterium,  Nocardia and

Rhodococcus  species), termed the CMN

group, constitute a very heterogeneous group;

however, most of the species share partic-

ular characteristics, such as: (i) a specific

cell wall organization, mainly character-

ized by the presence of a huge polymer

complex composed of peptidoglycan, ara-

binogalactan and mycolic acids [5, 26–28,

39, 45, 48] and (ii) high G+C content (47–

74%) [39, 40, 43, 80]. The genomes of sev-

eral species of this group have already been

completely sequenced; this fact reflects the

considerable medical, veterinary and bio-

technological importance of these organ-

isms (Tab. I).

Corynebacterium pseudotuberculosis is

an important animal pathogen. It is the eti-

ological agent of a disease that is commonly

called caseous lymphadenitis (CLA) or

cheesy gland [114]. This disease is found in

all the world’s major sheep and goat pro-

duction areas, causing significant eco-

nomic losses [85, 114].

In this review, we present the main

microbiological characteristics of C. pseu-



dotuberculosis. Bacterial virulence deter-

minants, including previously reported vir-

ulence factors and recently identified

molecules, are discussed, with emphasis on

the molecular strategies that have been used

to identify and study such determinants.

The aspects regarding CLA are also cov-

ered, focusing on the currently-available

commercial and experimental vaccines.

2. MICROBIOLOGICAL, 

BIOCHEMICAL AND 

TAXONOMIC FEATURES OF 

C. PSEUDOTUBERCULOSIS

2.1. Microbiological aspects

C.

 pseudotuberculosis was isolated from

bovine farcy in 1888 by Nocard. Preisz, in

1894, was the first to completely describe

this microorganism and to observe its

resemblance to the diphtheria bacillus.

Synonyms for C. pseudotuberculosis were



Bacillus pseudotuberculosis ovisBacillus

pseudotuberculosisCorynebacterium ovis

and Preisz-Nocard bacillus [59, 72].

This microorganism is a facultative

intracellular pathogen that exhibits pleo-

morphic forms, such as coccoids and fila-

mentous rods, ranging in size from 0.5 

μm

to 0.6 


μm by 1.0 μm to 3.0 μm [17, 28, 72,

97]. It is a non-sporulating, non-capsulated

and non-motile bacterium; however, it has

fimbriae [17, 46, 72]. This bacterium is a

facultative anaerobe and grows best at


The role of C. pseudotuberculosis in pathogenesis

203


37 °C, at a pH of 7.0 to 7.2 [17, 72, 97]. It

grows sparse initially on the agar surface

and then becomes organized in clumps or in

palisades, taking on a cream to orange col-

oration; colonies are dry, opaque and con-

centrically ringed. Growth in fluid medium

develops as a granular deposit with a sur-

face pellicle [17, 72, 77]. Haemolysis on

blood agar is variable, but large zones

develop in the presence of Rhodococcus



equi [17]. C. pseudotuberculosis toxin

inhibits the action of staphylococcal 

β-lysin

[59].


C. pseudotuberculosis stains Gram-

positive and when stained by Albert’s or

Neisser’s method, volutin granules can be

visualized. These metachromatic granules

are clearly observed in the bacillary form,

but are absent from coccoid cells; they con-

tain high-energy phosphate reserves [46,

72].


2.2. Biochemical properties

Cell wall peptidoglycan is based on



meso-diaminopimelic acid (meso-DAP).

Arabinose and galactose are major cell wall

sugars. Short-chain mycolic acids (coryno-

mycolic acids, 22–36 carbon atoms) are

present [59, 94, 97]. Biochemical reactions

of C. pseudotuberculosis isolates vary con-

siderably, mainly in their fermenting ability

[72, 100, 105]. All strains produce acid, but

not gas, from many carbon sources, includ-

ing glucose, fructose, maltose, mannose,

and sucrose [17, 53, 59, 72]. This bacterium

is phospholipase D and catalase positive,

oxidase negative, and it is beta-hemolytic

[59, 77, 100]. Strains isolated from small

ruminants generally do not reduce nitrate

[17, 72, 100, 114].

A well-established biochemical test for

coryneform bacteria identification is the

API Coryne system (API-bioMérieux, Inc.,

La Balme les Grottes, France). This method

consists of 21 biochemical tests; it can be

performed in 24–48 h. The test contains

20 tubes containing substrates that allow

for 11 enzyme tests (pyrazinamidase,

pyrrolidonyl arylamidase, 

β-galactosidase,

alkaline phosphatase, 

α-glucosidase,  N-

acetylglucosaminidase, 

β-glucuronidase, and

nitrate reduction and gelatin, urea and escu-

lin hydrolysis) and eight carbohydrate fer-

mentation tests (glucose, ribose, D-xylose,

mannitol, maltose, lactose, sucrose and gly-

cogen). This system is more reliable and

rapid when it is compared with standard

identification methods (API-bioMérieux,

Inc.). A summary of general biochemical

properties of C. pseudotuberculosis is pre-

sented in Table II. 



2.3. Antimicrobial susceptibility

The susceptibility pattern of C. pseudo-



tuberculosis to antimicrobial agents varies

among isolates obtained from various

sources [28, 37, 66]. Muckle and Gyles

[77], in a study of 26 strains isolated from

lesions of caseous lymphadenitis in goats,

reported that all strains were susceptible to

the antibiotics ampicillin, chlorampheni-

col, lincomycin, gentamicin, tetracycline,

penicillin G and sulfamethoxazole-trimeth-

oprim. Only three isolates were susceptible

to neomycin, and all strains were resistant

to streptomycin. Garg et al. [40] reported

strains of C. pseudotuberculosis that were

strongly resistant to penicillin but suscepti-

ble to neomycin. A strain highly resistant to

streptomycin (500 

μg/mL) was observed in

a study of 22 isolates of C. pseudotubercu-



losis from sheep and goat abscesses [90].

Minimal inhibitory concentration (MIC)

values for all isolates were similar for the

various antimicrobial agents. Later studies

also indicated a similarity of MIC values

among strains [1, 29, 60]. However, Fern-

ández et al. [35] found higher MIC values

for several antimicrobial agents, in an anal-

ysis of corynebacteria isolated from ewe

mastitis.

Olson et al. [82] grew C. pseudotuber-

culosis as a biofilm, in an attempt to repro-

duce the environment of a natural infection.

They observed that this bacterium was

highly resistant to all the drugs that they

tested under such growth conditions.


204

F.A. Dorella et al.



Ta

b

le

 I

The main representati

v

es of


 the 

CMN 


group.

Rep


re

se

n



ta

ti

v



e

St

at



us

Im

po



rt

an

ce



S

eq

u



en

ced 


str

ai

n



Ge

no

me size



 

(M

bp)



GC 

con


te

n

ts



 

(%)


Re

fe

re



n

ce

C



o

ry

ne

ba

ct

er

iu

m

 

di

ph

th

er

ia

e

C

o



mp

lete


Cau

sa

l ag



en

t o


th

e d



ise

as

e d



ip

h

th



er

ia

 in h



u

ma

ns



N

CTC 


13

12

9



2.

48

8



5

3

[20



]

C

o

ry

ne

ba

ct

er

iu

m

 

ef

fi

ci

ens

C

o



mp

le

te



Pr

od

uct



io

n

 of



 g

lu

ta



m

at

e an



d o

ther


 a

m

ino 



ac

id

s a



n

d

 



co

mpo


und

s

YS-



3

1

4



3.

14

7



6

3

[81



]

C

o

ry

ne

ba

ct

er

iu

m

 

gl

ut

ami

cum

Co

m



p

le

te



P

ro

d



u

ctio


n o

f gl


ut

am

at



e,

 ot


he

r a


m

in

o



 ac

id

s (L



-l

ys

in



e) a

n

d



 

co

mpo



und

s

A



TCC

 

13



03

2

3.



30

9

5



3

[55


]

Myco

ba

ct

er

iu

m a

vi

u

m

In

 p



ro

g

re



ss

Cau


se

s tu


be

rc

ul



os

is

 i



n

 bi


rd

s an


d

is



se

mi

na



te

d in


fe

ct

ions



 i

n

 



imm

u

n



oco

mpr


o

m

iz



ed

 hu


man

(t



he

 el


d

er

ly



, ch

il

d



re

n



an

es



pe

ci

al



ly

 p

at



ient

s wi


th

 AI


DS)

10

4



5

.4

80



68

h

ttp



://

www


.ti

gr

.o



rg

/t

db



/

m

d



b/

md

b



inp

ro

gr



es

s.

h



tm

l

Myco



ba

ct

er

iu

m a

vi

u

m

su

bs



p. 

pa

ra

tub

er

cu

lo

sis

Co

m



p

le

te



C

aus


ati

v

e ag



en

t o


f Jo

hn

e’



s di

se

as



e,

 or


 pa

ra

tu



be

rc

ulo



si

s,

 a 



ch

ro

ni



c s

ev

er



e i

n

te



st

in

al



 in

fe

ct



io

n

. Th



e d

ise


as

e a


ff

ec

ts



 

do

mes



ti

c an


d f

re

e-



rang

ing 


ru

mi

nan



ts

b



u

t ha


al

so



 be

en

 



re

po

rt



ed

 i

n



 p

ri

m



at

es

, ra



bb

it

s,



 s

to

at



s an

d f


o

x

es



k1

0

4



.8

29

69



[8

8]

Myco



ba

ct

er

iu

m b

o

vi

s

C

o



mp

le

te



Cau

sa

ti



v

e age


nt

 of


 c

la

ss



ic 

b

o



v

ine


 t

u

b



er

cul


o

si

s, 



b

u

t it



 ca

n al


so

 

ca



u

se

 th



e d

ise


as

e in


 hu

m

an



s,

 es


pe

ci

al



ly i

f co


nt

am

in



at

ed

 m



ilk

 

is



 c

ons


um

ed 


wi

th

ou



pr

io



pas


te

u

ri



za

ti

o



n. T

h

is



 is

 a

 fu



ll

y

 



vi

ru

lent



 s

tra


in

AF2


122

/9

7



4

.3

4



5

6

5



h

tt

p



:/

/www


.s

an

ge



r.

ac

.uk



/

P

ro



ject

s/

M_



bo

vi

s/



[4

1]

Myco



ba

ct

er

iu

m b

o

vi

s

In

 p



ro

g

re



ss

Cau


sa

ti

v



e age

nt

 of



 c

la

ss



ic 

b

o



v

ine


 t

u

b



er

cul


o

si

s, 



b

u

t it



 ca

n al


so

 

ca



us

e t


h

e di


se

as

e i



n

 h

u



ma

ns

. Th



is

 i

s t



he 

st

ra



in

 t

h



at

 i

s u



se

d

 to



 

pr

od



uce

 BC


G (

B

ac



il

le

 de 



Cal

m

et



te

 et


 Gu

èr

in



) v

acci


n

e, a


 

w

ell-



kn

o

w



n

 tu


be

rc

ul



os

is v


ac

ci

n



e

BCG


4

.4

0



0

5

7



h

ttp


://

www


.p

as

teu



r.

fr

/



re

ch

er



ch

e/

un



ite

s/

Lg



m

b

/



myc

oge


no

mi

cs



.ht

m

Myco



ba

ct

er

iu

m l

epr

ae

Co

m



p

le

te



C

aus


ati

v

e ag



en

t o


f hu

m

an



 lep

ro

sy



T

N

3



.2

68

57



[3

8]

Myco



ba

ct

er

iu



sme

g

ma

ti

s

In

 p



ro

g

re



ss

Gen


er

al

ly



 no

n-

pa



th

og

eni



m

yco



ba

ct

er



iu

m ca


pa

bl

e o



f ca

us

ing 



so

ft

 tis



su

e le


si

on

s. This



 ba

ct

er



ium w

as in


iti

all


y

 is


ol

ate


d

 f

ro



m

 

hu



man

 sme


g

m

a. 



It

 i



as

so

ci



at

ed

 wi



th

 s

o



ft

 ti


ss

u

e l



esi

on



fo

ll

o



w

in

g t



rau

ma o


su

rg



er

y

MC2



 15

5

7



.0

40

57



h

ttp


://

www


.ti

gr

.o



rg

/t

db



/

m

d



b/

md

b



inp

ro

gr



es

s.

h



tm

l


The role of C. pseudotuberculosis in pathogenesis

205


Download 357.03 Kb.

Do'stlaringiz bilan baham:
  1   2   3   4




Ma'lumotlar bazasi mualliflik huquqi bilan himoyalangan ©fayllar.org 2024
ma'muriyatiga murojaat qiling