Environmental and Molecular Mutagenesis - Legacy Tobacco ...

Arg'His*Thr* .Examination of the pattern of amber and oohre T4 baoteriophage
suppression indicate that the reversion to Arg+His Thr in AB
2497 may be the result of su B and ~eu Eoc suppressor formation (whioh
^an arise by a GC 4 AT tranion)•re~as the reversion to Arg*Hie•
rhr* may be the result of g1tY or fxs-4 suppressor formation (which
can arise by a GC (or AT) -~- TA traneversion) The frequency of El13-induced
Arg* reversion is little dependent either on umuC or mutS .
The mechanism of the different specificity of EUS-in ueed m-0s$ione
will be discussed .
271
MULTIPLE END POINTS FOR SOMATIC MUTATIONS IN HUMANS PROVIDE
COMPLEMENTARY VIEWS FOR BIODOSIMETRY, GENOTOXICITY, AND
HEALTH RISKS
R .H . Jensen, W .L. Bigbee, and R.G . Langlois, Biomedical Sciences Division,
Lawrence Livermore National Laboratory, Livermore, CA 94550
Recent technologic developments now allow us to measure genotoxic effects of human
exposure to mutagenic phenomena In four different ways--HPRT mutations in lymphocytes,
HLA mutations on the surface of lymphocytes, hemoglobin variant mutations In
erythrocytes, and glyoophorin A mutations on the surface of erythrocytes . Each of these
assay methods shows advantages and disadvantages In being used to monitor for
exposure of individuals to mutagenic phenomena such as toxic chemicais or Ionizing
radiation . For example, the techniques used for the lymphocyte-based assays can be
extended to isolate nuclear DNA and characterize the mutagenic changes that have
occurred, while erythrocytes contain no DNA for such analyses . On the other hand, the
erythrocyte-based assays are probing a tissue in which differentiation Is straight forward
and clearly delineated, whereas lymphocytes display complex and muRi-organ
developmental pathways . Thus, using combinations of these assays (and others as they
develop) for each individual should furnish a set of monitoring data that can be broadly
interpreted to provide biodosimetrks Information and potential estimates of cancer risk . The
impact of obtaining such information is high enough to justify the challenge of performing
mufti-end point analyses on populations at high risk for mutagenic exposure .
272
GpNOTOXICI7Y OF 23 C}ICMCAIS TO S GFREVLSIAE
li ang Z„oshu et at
A .-parennt of Biology. Sooond Mitlifary Medical thriwsity, Shanghai, CMna
23 kinds or danicals vNne used to evaluate the edidettcy of S ans4sias as a toot in the assay of genotopns
The growing cells ar S aaevimac D7 wero treatod with thatdcels at 28°C for 6 houtz As te~oAOd eonte known
mutagens such as MNNG, 4-NQO and hydroxytmea oould inoease the firqtta>cy of ttp oarvertants _ to
3-10 t6rts, and we also found that same pvnulagw such as cyclopl~osp}rvnidc andtrypon btue could iitacase
the froqua~y to s-10 times without any exogatotn adivation 'iltis itd'~caled that the yeast may
cndogawuclY me~aboli~e prcmutagens into teadlre intanndiatea lt wat sepottod that mme eatdttopens had a
false-ncgaGw iesportst in Amca trst, twl in our experinrnt 3l evas shatm lhat Q 1-Q 3•/% anihne muld lncrease
Ux frcqua~y ot gene oonNersion in1tp Ioats to 1-3 4 tirrrs, 15-30 tng/ml aiodnic anhydride 1 .4-A 1 tanea,
10-80 mM trypan biue 1-4 Gntca, Q 12-Q 4 M thioutt8l S-7 . S timx atd a2 -Q S•/. prhott Iettachlatide
2 . 5-10 tirnes AdditionaRy , the intertupt prooodt~ was tssod to aaoen the indttoaa or ehrornason~e
mahr~a fion The growing odls of S oaetidae D6L M t+ere irtated with diatticah at 28'C for 4 hottn, then
at 0 C for 16 hours and again ,at 28°C for 4 twun brloee piatod wilh the tmditun oontaininnY Q S µg/m)
cydoheuamide The fioqtrawy ot the while lettdne-ra1 oolonra tepresetttod Ihat of chrarnosatte loss It
was shown that some chanicais such as methyl nntitae,jlate~oould catne ctunsttasorne loes We aostdudod that
the S annisiae has a unique tac~~ulrcss in the aaay of gs,otapts
273
ANTIMUPAGENICITY OF CHINESE MEDICiNES .
Tiang Zuoshu, WangUngh ua and Chen Zhongfu
Dcpartmrnt of Biaiogy. Seoord Military Modiesl Lhtiversity and Institute of Gcnctics, Fudan L)niversity, Shan ;ha't
Chma
In order to study the antimutaganaty of Cldnese modidncs, the Inductest was uud to saern the inh'hiton of SO6
re;ponsc homar~ang 601rnds of Clmiete rnodidr~, as it has tzen known that SOS response ptays an important role
m mutagrnese. A IItu paper disc with 10 yt of 0. 1 mg/mt of Mitomydn C (MMC) and another one with the estract
of Qiinese momcnie wce put 1 an apart on the surfem of the top agar containing both the Absogc* E[xa6
acII ( GY5027) and the udieator E aiticd (GY4015) . Aller the plate was incubated at 3NC for 8 hours, phage
plaques appeared around the MMC diu, and a partial afipse of SOS hile'hition ( with roplaque or darcased ntmber
of plaque) would appear bdwern the two disc if the Ci :nae iiiediaie estract in tho disc had an inhibitory edax on
SOS response The results showod that 11 kinds of Chineae nmbdnes had such an eQoct. Sane of than were further
studiod with SOS dvamotest. In this test, the growing od af E ca6 PQ37 was exposed to U K and incvbated in LB
http://legacy.library.ucsf.edu/tid/clb93d00/pdf
1989 EMS Abstracts 95
Notes